Install ISPConfig on CentOS 8 with Apache, PHP, Postfix, Dovecot, Pure-FTPD, BIND

This article covers how to install and configure ISPConfig on a CentOS 8 server. In fact, with ISPConfig installed, you can manage a variety of services, administer multiple servers, and designate different authorization levels for server administrators, all from the familiarity and comfort of any modern browser.

Install OpenProject on Debian 11 - Step by step guide ?

This article covers how to install and configure OpenProject on Debian 11. In fact, OpenProject provides a simple and easy-to-use web interface that allows you to collaborate on projects using features such as a WYSIWYG text editor, intelligent workflows, conditional formatting, team collaboration, Kanban, Agile & Scrum, project planning and scheduling, time tracking, product roadmaps, and release planning.

Install LibreNMS Monitoring Tool on Debian 11 - Step by step guide ?

This article covers the complete procedure for installing the latest version of LibreNMS network monitoring system on Debian 11 Bullseye. In fact, LibreNMS is an auto discovering PHP/MySQL-based network monitoring system that includes support for a wide range of network hardware and operating systems including Cisco, Linux, FreeBSD, Juniper, Brocade, HP, and many more.

Migrate Centos 8 to AlmaLinux 8.3 - Step by step guide ?

This article covers the complete procedure for upgrading your CentOS 8 to AlmaLinux 8. In fact, AlmaLinux OS is an open-source, community-driven project that intends to fill the gap left by the demise of the CentOS stable release. With this system, You can rely on AlmaLinux OS to run you and your client's critical workloads.

Configuring Postfix to Use Gmail as SMTP server on Ubuntu 18.04

This article will guide you on the step by step process you need to follow to Set up #postfix to use #gmail as #smtp server on #Ubuntu 18.04

Migrating Zabbix from one Linux server to another

This article will help you to migrate Zabbix from one Linux server to another (Centos to Debian).

cPanel error networkmanager is installed and running

This article covers how to resolve the error, NetworkManager is installed and running. Basically, this error happens if cPanel does not support NetworkManager-enabled systems.


To fix this error, simply run the commands below and then restart the installation of cPANEL:

$ systemctl stop NetworkManager.service
$ systemctl disable NetworkManager.service

Install Wazuh Server on CentOS 7 - Step by Step Process ?

This article covers the installation procedure of Wazuh Server on CentOS Linux System. Basically, Wazuh is a free, open-source and enterprise-ready security monitoring solution for threat detection, integrity monitoring, incident response and compliance. 


You can use Wazuh for the following applications:

  • Security analysis
  • Log analysis
  • Vulnerability detection
  • Container security
  • Cloud security


To Install Java on CentOS 8.

1. Run the command below to install JDK:

$ sudo dnf install java-11-openjdk-devel

2. Confirm that you have it installed

$ java -version

NRPE Command Plugin Not Defined - How to fix it ?

This article covers methods to resolve 'NRPE Command Plugin Not Defined' for our customers.

This error is very straight forward. Usually this is caused by a mismatch between the command name declared in Nagios XI to be check through NRPE and the actual command name of the command directive in the remote host's nrpe.cfg file.

This problem will occur in versions of check_nrpe before v3. 

What is happening here is that the initial -c check_users is being overwritten by the -a -w 5 -c 10, as check_nrpe thinks the -c 10 argument is the command argument, not one of the -a arguments.

Install PHP 8 on CentOS 7 / CentOS 8 - Step by Step Process ?

This article covers how to install PHP 8.0 on CentOS 8/7 and RHEL 8/7.

PHP is the most used scripting language for web development, both websites and web applications.

This guide will show you how to install PHP 8.0 on CentOS 8 | CentOS 7. 

Please note the GA release is fit for running in Production if the application already supports it.


To install any additional PHP package use command syntax:

$ sudo yum install php-xxx

To Check PHP version:

$ php --version

Install Docker CE on AlmaLinux 8 - Step by Step Process ?

This article covers step by Step process to install Docker CE on AlmaLinux.

Docker is a tool that is used to run software in a container.

It's a great way for developers and users to worry less about compatibility with an operating system and dependencies because the contained software should run identically on any system.


To Install Docker on AlmaLinux:

1. We can add the Docker repository to our system with the following command.

$ sudo dnf config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo

2. Before we begin installing Docker, we need to remove the podman and buildah packages from our system, as they conflict with Docker and will inhibit it from being installed.

$ sudo dnf remove podman buildah

3. Finally, we can install the three Docker packages we'll need by executing the following command.

$ sudo dnf install docker-ce docker-ce-cli containerd.io

4. Once installation is completed, start the Docker service and, optionally, enable it to run whenever the system is rebooted:

$ sudo systemctl start docker.service
$ sudo systemctl enable docker.service

5. You can verify that Docker is installed and gather some information about the current version by entering this command:

$ sudo docker version

Enable EPEL repository on AlmaLinux 8 - Step by Step Process ?

This article covers how to enable EPEL repository on AlmaLinux 8.

Extra Packages for Enterprise Linux (EPEL) is repository with a high quality set of additional packages for Enterprise Linux operating systems such as Red Hat Enterprise Linux (RHEL), CentOS and Scientific Linux (SL), Oracle Linux (OL), AlmaLinux and any other Linux distribution from the RHEL family.


Run the command below to install EPEL Repository on AlmaLinux OS 8:

# sudo yum install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm

Accept installation using the y key.

Install WHM Cpanel on AlmaLinux 8 Server - Step by Step Process ?

This article covers the complete steps to install WHM Cpanel on AlmaLinux 8 Server.

To manage Linux servers for hosting purposes most of the services are using WHM's Cpanel.

Although there are many hosting manager software, because of its easy-to-use interface and features, it is one of the best control panels for Web hosting services. 


cPanel, Control Panel, is a control panel developed in 1997 that offers us high-quality web hosting with excellent features that, thanks to WHM (Web Host Manager), can be managed from a graphics console, with everyone doing their job.

Install NDOUtils in CentOS RHEL and fix related error

This article covers how to install NDOUtils in CentOS. NDOUtils is an addon for Nagios Core that allows you to export current and historical data from one or more Nagios Core instances to a MySQL database. NDOUtils is included with Nagios XI. A source in Nagios Network Analyzer is the data collector. Outside of Nagios Network Analyzer a source is the location where data is originating from.


NDOUtils uses the kernel message queue for transferring the data from Nagios to NDOUtils. We are going to increase the default values the Kernel boots with to ensure it operates optimally.

1. Downloading NDOUtils Source

cd /tmp

wget -O ndoutils.tar.gz https://github.com/NagiosEnterprises/ndoutils/releases/download/ndoutils-2.1.3/ndoutils-2.1.3.tar.gz

tar xzf ndoutils.tar.gz

2. Compile NDOUtils

cd /tmp/ndoutils-2.1.3/

./configure

make all

3. Install Binaries

This step installs the binary files.

make install

4. Initialize Database

This prepares the database for NDOUtils.

cd db/

./installdb -u 'ndoutils' -p 'ndoutils_password' -h 'localhost' -d nagios

cd .. 

Welcome to Emergency mode in Linux - Fix this boot error now

This article covers how to fix boot error, Welcome to Emergency mode in Linux. This issue happens after an emergency power outage on a server, a system crash, or similar situations.


The Emergency Mode sometime means that your file system may be corrupted.

In such cases, you will be left out with a prompt to go nowhere.

All you have to do is perform a file system check using,

fsck.ext4 /dev/sda3

where sda3 can be your partition and if you are using ext3 file system, change the command as follows:

fsck.ext3 /dev/sda3

About the partition number, Linux shows you the partition before arriving at the prompt.

This should solve the problem.


To fix  Emergency Mode On Ubuntu:

1. use Ubuntu Live USB to boot, and open terminal:

$ sudo fsck.ext4 /dev/sda3

2. Adding sudo because it needs root permission.

(Replace ext4 with ext3 if applicable to you)

3. Cycle through the SDAs by changing the last number in the sda to see which file system has problems.

Ex: sda1, sda2, sda3, sda4, and so on

4. As I encountered, the problem might be with the 'home' directory.

5. Once you run the above command, you'll be prompted to fix the issue right inside the terminal itself.

6. Keep hitting y (for yes) until the end of the fix.

(or you can use -fy for automatically response yes to all.)

7. Navigate to the home folder of your sda using your files explorer.

(This will be mounted from the HDD since you are working with a Live USB)

8. Check inside 'home' if you can see all your files. If yes, then you're ready to reboot to your system (remove the Live USB).

Files and Processes in SELinux on CentOS 7 - More information

This article covers Files and Processes in SELinux. Basically, managing file and process context are at the heart of a successful SELinux implementation.

With SELinux, a process or application will have only the rights it needs to function and NOTHING more. The SELinux policy for the application will determine what types of files it needs access to and what processes it can transition to. 

SELinux policies are written by app developers and shipped with the Linux distribution that supports it. A policy is basically a set of rules that maps processes and users to their rights.


SELinux enforces something we can term as “context inheritance”. What this means is that unless specified by the policy, processes and files are created with the contexts of their parents.

So if we have a process called “proc_a” spawning another process called “proc_b”, the spawned process will run in the same domain as “proc_a” unless specified otherwise by the SELinux policy.


SELinux in Action: Testing a File Context Error

1. First, let's create a directory named www under the root. We will also create a folder called html under www:

mkdir -p /www/html

 

2. If we run the ls -Z command, we will see these directories have been created with the default_t context:

ls -Z /www/

drwxr-xr-x. root root unconfined_u:object_r:default_t:s0 html


3. Next we copy the contents of the /var/www/html directory to /www/html:

cp /var/www/html/index.html /www/html/

 

The copied file will have a context of default_t. That's the context of the parent directory.


We now edit the httpd.conf file to point to this new directory as the web site's root folder. 

i. We will also have to relax the access rights for this directory.

vi /etc/httpd/conf/httpd.conf

ii. First we comment out the existing location for document root and add a new DocumentRoot directive to /www/html:

# DocumentRoot "/var/www/html"

DocumentRoot "/www/html"

iii. We also comment out the access rights section for the existing document root and add a new section:

#<Directory "/var/www">

#    AllowOverride None

    # Allow open access:

#    Require all granted

#</Directory>


<Directory "/www">

    AllowOverride None

    # Allow open access:

    Require all granted

</Directory>


We leave the location of the cgi-bin directory as it is. We are not getting into detailed Apache configuration here; we just want our site to work for SELinux purposes.


iv. Finally, restart the httpd daemon:

service httpd restart

 

Once the server has been restarted, accessing the web page will give us the same “403 Forbidden” error (or default “Testing 123” page) we saw before.

The error is happening because the index.html file's context changed during the copy operation. It needs to be changed back to its original context (httpd_sys_content_t).

restorecond Will not restore a file with more than one hard link - How to resolve this issue

This article covers Tips to fix 'restorecond: Will not restore a file with more than one hard link' error.

To fix this problem type the following commands:

# rm /etc/sysconfig/networking/profiles/default/resolv.conf

# restorecon /etc/resolv.conf

# ln /etc/resolv.conf /etc/sysconfig/networking/profiles/default/resolv.conf

dhclient to persistently look for an IP address lease - Configure it Now

This article covers how to use dhclient command. Basically, Linux dhclient command can provide an IP lease until DHCP Server/Router grants one.

With this guide, you can easily configure Linux dhclient command to continuously requests an IP lease until one is granted by DHCP Server / Router.

Create CentOS Fedora RHEL VM Template on KVM - How to do it

This article covers how to create CentOS/Fedora/RHEL VM Templates on KVM. VM Templates are more useful when deploying high numbers of similar VMs that require consistency across deployments. If something goes wrong in an instance created from the Template, you can clone a fresh VM from the template with minimal effort.


To install KVM in your Linux system:

The KVM service (libvirtd) should be running and enabled to start at boot.

$ sudo systemctl start libvirtd

$ sudo systemctl enable libvirtd

Enable vhost-net kernel module on Ubuntu/Debian.

$ sudo modprobe vhost_net

# echo vhost_net | sudo tee -a /etc/modules


How to Prepare CentOS / Fedora / RHEL VM template ?

1. Update system

After you finish VM installation, login to the instance and update all system packages to the latest versions.

$ sudo yum -y update

2. Install standard basic packages missing:

$ sudo yum install -y epel-release vim bash-completion wget curl telnet net-tools unzip lvm2 

3. Install acpid and cloud-init packages.

$ sudo yum -y install acpid cloud-init cloud-utils-growpart

$ sudo sudo systemctl enable --now acpid

4. Disable the zeroconf route

$ echo "NOZEROCONF=yes" | sudo tee -a /etc/sysconfig/network

5. Configure GRUB_CMDLINE_LINUX – For Openstack usage.

If you plan on exporting template to Openstack Glance image service, edit the /etc/default/grub file and configure the GRUB_CMDLINE_LINUX option. Your line should look like below – remove rhgb quiet and add console=tty0 console=ttyS0,115200n8.

GRUB_CMDLINE_LINUX="crashkernel=auto rd.lvm.lv=cl/root rd.lvm.lv=cl/swap console=tty0 console=ttyS0,115200n8"

Generate grub configuration.

$ sudo grub2-mkconfig -o /boot/grub2/grub.cfg

6. Install other packages you need on your baseline template.

7. When done, power off the virtual machine.


How to Clean VM template ?

You need virt-sysprep tool for cleaning the instance.

$ sudo virt-sysprep -d centos7

Add Compute Host to oVirt Virtualization - How to do it

This article covers oVirt Virtualization and how to add Compute Host to oVirt Virtualization. oVirt is a free and open-source distributed virtualization solution that can be used to manage your entire infrastructure.

oVirt allows you to manage virtual machines, compute, storage and networking resources from the web-based interface. It uses KVM hypervisor and built upon several other community projects, including libvirt, Gluster, PatternFly, and Ansible.


To Add Compute Host to oVirt:

1. Validate oVirt Engine installation by logging into the console.

2. Navigate to Compute > Hosts > New and fill all required information.

3. Modify other settings in the left panel as you see fit and click "OK" button to provision the node.

4. The Status should change to Installing and will finish in few minutes.


To Configure Host Networking:

1. If you want to add additional networks – extra bridges with VLANs e.t.c, this can be done once the host is added.

2. First create a Logical Network on Network > New. Give Virtual Network correct details. For VLAN ID check "Enable VLAN tagging".

3. With the Host added and active you can configure its networking under Network Interfaces > Setup Host Networks.

4. Assign the Logical network to an interface.

5. Drag Virtual Network for mapping to host interface.

6. Configure IP addressing if required.

7. Once saved and successful it should turn green.

8. You can then proceed to create virtual machines using oVirt Management interface.

SELinux users on CentOS 7 – Actions and Deciphering error messages

This article covers more information about SELinux users on CentOS 7.


Deciphering SELinux Error Messages

We looked at one SELinux error message. We were then using the grep command to sift through /var/log/messages file. Fortunately SELinux comes with a few tools to make life a bit easier than that. These tools are not installed by default and require installing a few packages, which you should have installed in the first part of this tutorial.

The first command is ausearch. We can make use of this command if the auditd daemon is running. In the following code snippet we are trying to look at all the error messages related to the httpd daemon. Make sure you are in your root account:

ausearch -m avc -c httpd

In our system a number of entries were listed, but we will concentrate on the last one:

----
time->Thu Aug 21 16:42:17 2014
...
type=AVC msg=audit(1408603337.115:914): avc:  denied  { getattr } for  pid=10204 comm="httpd" path="/www/html/index.html" dev="dm-0" ino=8445484 scontext=system_u:system_r:httpd_t:s0 tcontext=unconfined_u:object_r:default_t:s0 tclass=file

Even experienced system administrators can get confused by messages like this unless they know what they are looking for. To understand it, let’s take apart each of the fields:

type=AVC and avc: AVC stands for Access Vector Cache. SELinux caches access control decisions for resource and processes. This cache is known as the Access Vector Cache (AVC). That's why SELinux access denial messages are also known as “AVC denials”. These two fields of information are saying the entry is coming from an AVC log and it’s an AVC event.


denied { getattr }: The permission that was attempted and the result it got. In this case the get attribute operation was denied.

pid=10204. This is the process id of the process that attempted the access.

comm: The process id by itself doesn’t mean much. The comm attribute shows the process command. In this case it’s httpd. Immediately we know the error is coming from the web server.

path: The location of the resource that was accessed. In this case it’s a file under /www/html/index.html.

dev and ino: The device where the target resource resides and its inode address.

scontext: The security context of the process. We can see the source is running under the httpd_t domain.

tcontext: The security context of the target resource. In this case the file type is default_t.

tclass: The class of the target resource. In this case it’s a file.

Install PowerDNS and PowerAdmin on CentOS 7 - How to do it

This article covers the step by step procedure to install PowerDNS on CentOS 7. PowerDNS (pdns) is an open source DNS server written in C++ and released under GPL License. It has become a good alternative for the traditional DNS server Bind, designed with better performance and low memory requirements. 

PowerDNS provides two products, the Authoritative server, and the Recursor. 

The PowerDNS Authoritative server can be configured through the different backend, including the plain Bind zone files, RDBMS such as MySQL, PostgreSQL, SQLite3 or LDAP.


To Install PowerDNS on CentOS 7:

1. First let's start by ensuring your system is up-to-date:

$ yum clean all

$ yum -y update

2. Install PowerDNS and backend.

First, you need to enable EPEL repository and all required packages on your system:

$ yum install epel-release

$ yum install bind-utils pdns pdns-recursor pdns-backend-mysql mariadb mariadb-server

Enable PowerDNS on boot and start PowerDNS server:

$ systemctl enable mariadb

$ systemctl enable pdns

$ systemctl enable pdns-recursor

3. Configure MariaDB.

By default, MariaDB is not hardened. You can secure MariaDB using the mysql_secure_installation script. you should read and below each steps carefully which will set root password, remove anonymous users, disallow remote root login, and remove the test database and access to secure MariaDB:

mysql_secure_installation

4. Create PowerDNS Database and User in MariaDB.

Login as a MariaDB root and create a new database and tables:

### mysql -uroot -p

5. Configure PowerDNS.

Open the /etc/pdns/pdns.conf file.

Finally, restart the Power DNS service:

$ systemctl restart pdns.service

$systemctl enable pdns.service

6. Configure Recursor.

Open the /etc/pdns-recursor/recursor.conf file.

Add Remote Linux Host to Cacti for Monitoring - Do it now

This article covers how to add a #Linux host to #Cacti.

Basically, Cacti is a network #monitoring device that creates personalized graphs of server efficiency.

SNMP, short for Simple Network Management Protocol is a protocol used for gathering information about devices in a network. Using SNMP, you can poll metrics such as CPU utilization, memory usage, disk utilization, network bandwidth, and so on. 


To install snmp agent on Ubuntu, run the command:

$ sudo apt install snmp snmpd -y


To install #snmp agent On CentOS 8, run the command:

$ sudo dnf install net-snmp net-snmp-utils -y


SNMP starts automatically upon installation.

To confirm this, confirm the status by running:

$ sudo systemctl status snmpd

If the service is not running yet, start and enable it on boot as shown:

$ sudo systemctl start snmpd


To Add Remote Linux Host to Cacti for Monitoring:

1. Install SNMP service on Linux hosts. SNMP, short for Simple Network Management Protocol is a protocol used for gathering information about devices in a network.

2. Configuring SNMP service.

3. Configure the firewall rules for snmp.

4. Adding remote Linux host to Cacti.


To Install and Configure Cacti:

1. Cacti require few more dependencies, run the following command to install them:

yum -y install net-snmp rrdtool net-snmp-utils

2. As we have all the dependencies ready, we can now download the install package from Cacti website.

cd /var/www/html

wget http://www.cacti.net/downloads/cacti-1.1.10.tar.gz

3. You can always find the link to the latest version of the application on Cacti download page. Extract the archive using the following command.

tar xzvf cacti*.tar.gz

4. Rename your Cacti folder using:

mv cacti-1*/ cacti/

5. Now import the Cacti database by running the following command.

cd /var/www/html/cacti

mysql cacti_data < cacti.sql -u root -p

6. The above command will import the cacti.sql database into cacti_data using the user root. 

It will also ask you the password of root user before importing the database.

7. Now edit Cacti configuration by running the following command.

nano /var/www/html/cacti/include/config.php

8. Now find the following lines and edit them according to your MySQL database credentials.

/* make sure these values reflect your actual database/host/user/password */

$database_type     = 'mysql';

$database_default  = 'cacti_data';

$database_hostname = 'localhost';

$database_username = 'cacti_user';

$database_password = 'StrongPassword';

$database_port     = '3306';

$database_ssl      = false;

SELinux on CentOS 7 - Set it up now

This article covers how to set up SELinux on #CentOS 7. #SELinux is a security mechanism built into the Linux kernel. Linux distributions such as CentOS, RHEL, and Fedora are equipped with SELinux by default.

SELinux improves server security by restricting and defining how a server processes requests and users interact with sockets, network ports, and essential directories.


To check SELinux mode:

The easiest way on how to check SELinux ( Security Enhanced Linux ) operation mode is to use getenforce command. 

This command without any options or arguments will simply print a current status SELinux operational mode. 

Furthermore, the current status of SELinux operational mode can be set permanently or temporarily.


To check whether SELinux is enabled or not:

1. Use the getenforce command. [vagrant@vagrantdev ~]$ getenforce Permissive.

2. Use the sestatus command.

3. Use the SELinux Configuration File i.e. cat /etc/selinux/config to view the status.


To configure SELinux to enforcing mode:

1. Open the /etc/selinux/config file in a text editor of your choice, for example: # vi /etc/selinux/config.

2. Configure the SELINUX=enforcing option: # This file controls the state of SELinux on the system.

3. Save the change, and restart the system: # reboot.


To enable SELinux without rebooting:

1. Changing the SELinux mode at run time. If SELinux is disabled it cannot be enabled without rebooting.

2. To detemine the current Mode of SELinux.

3. Changing the SELinux mode Permanently. In the /boot/grub/grub.conf file add a line: selinux=0.

4. Or in /etc/sysconfig/selinux change.


To permanently change mode to permissive:

1. Edit the /etc/selinux/config file as follows: # This file controls the state of SELinux on the system. # SELINUX= can take one of these three values: # enforcing - SELinux security policy is enforced.

2. Restart the system: $ reboot.

Install Monit monitoring system on CentOS 8 - How to do it

This article covers how to #install Monit on #Centos 8 system. Also, we dealt with how to configure Monit on Centos, adjusting the configuration and setting up alerts to notify the users.

#Monit is a free, open-source process supervision tool for Unix and Linux. With Monit, system status can be viewed directly from the command line, or via the native HTTP(S) web server. Monit is able to do automatic maintenance, repair, and run meaningful causal actions in error situations.


To enable web interface you need to make changes in monit configuration file. 

The main configuration file of monit located at /etc/monit. conf under (RedHat/CentOS/Fedora) and /etc/monit/monitrc file for (Ubuntu/Debian/Linux Mint). 

Monit is very easy to use nearly out of the box. By default, it is set up to check that services are running every 2 minutes and stores its log file in “/var/log/monit.


To Install Monit to monitor your server running CentOS:

1. Install EPEL repository: yum install epel-release yum update.

2. Install Monit: yum install monit.

3. Activate Monit to start automatically during the system boot and start it: systemctl enable monit systemctl start monit.


To #Install #Monit Package on #Ubuntu:

Run the commands given below;

sudo apt update

sudo apt install monit


After installing Monit, the commands below can be used to stop, start and enable Monit service;

sudo systemctl stop monit.service

sudo systemctl start monit.service

sudo systemctl enable monit.service

DirectAdmin error is not a valid username

This article covers tips to resolve DirectAdmin error: is not a valid username which happens if the username length of the account is larger than the value set in the DirectAdmin configuration file.
To fix DirectAdmin Admin Backup/Transfer restore error with no details,  try to restore to a number than 10 characters.
You have to edit directadmin configuration and set this variable.
[root@mx ~]# vi /usr/local/directadmin/conf/directadmin.conf
then edit max_username_length to larger value. I my example 20.
max_username_length=20

Manage Networking with NetworkManager in RHEL CentOS 8

This article covers NetworkManager daemon for managing the networking service to dynamically configure and control network devices and keep connections up and active when they are available.
Netstat is a command line utility that can be used to list out all the network (socket) connections on a system.
It lists out all the tcp, udp socket connections and the unix socket connections.
To reboot Linux using the command line: To reboot the Linux system from a terminal session, sign in or “su”/”sudo” to the “root” account.
Then type “ sudo reboot ” to reboot the box. Wait for some time and the Linux server will reboot itself.

To troubleshoot network connectivity with Linux server:
i. Check your network configuration.
ii. Check the network configuration file.
iii. Check the servers DNS records.
iv. Test the connection both ways.
v. Find out where the connection fails.
vi. Firewall settings.
vii. Check Host status information.

To change the hostname in Linux Ubuntu:
i. Type the following command to edit /etc/hostname using nano or vi text editor: sudo nano /etc/hostname. Delete the old name and setup new name.
ii. Next Edit the /etc/hosts file: sudo nano /etc/hosts.
iii. Reboot the system to changes take effect: sudo reboot.

To reinstall #network service in #Linux (#Ubuntu / #Debian):
i. Use the following command to restart the server networking service. # sudo /etc/init.d/networking restart or
# sudo /etc/init.d/networking stop # sudo /etc/init.d/networking start else # sudo systemctl restart networking.
ii. Once this done, use the following command to check the server network status.

KVM live migration to resolve performance issues

This article covers how to use KVM live migration to achieve load balancing which is important in a server virtualization system to maintain server performance.
Migration enables an administrator to move a virtual machine instance from one compute host to another. A typical scenario is planned maintenance on the source host, but migration can also be useful to redistribute the load when many VM instances are running on a specific physical machine.

Kernel-based Virtual Machine (KVM) is an open source virtualization technology built into Linux.
Specifically, KVM lets you turn #Linux into a #hypervisor that allows a host machine to run multiple, isolated virtual environments called guests or virtual machines (VMs).

Live migration of virtual machines is necessary when you need to achieve high-availability setups and load distribution.
The #KVM hypervisor has been a powerful alternative to Xen and VMware in the Linux world for several years.
To make the virtualization solution suitable for enterprise use, the developers are continually integrating new and useful features.
An example of this is live migration of virtual machines (VMs).

Live #migration involves:
The instance keeps running throughout the migration.
This is useful when it is not possible or desirable to stop the application running on the instance.
Live migrations can be classified further by the way they treat instance storage:
1. Shared storage-based live migration. The instance has ephemeral disks that are located on storage shared between the source and destination hosts.
2. Block live migration, or simply block migration. The instance has ephemeral disks that are not shared between the source and destination hosts. Block migration is incompatible with read-only devices such as CD-ROMs and Configuration Drive (config_drive).
3. Volume-backed live migration. Instances use volumes rather than ephemeral disks.

Block live migration requires copying disks from the source to the destination host.
It takes more time and puts more load on the network. Shared-storage and volume-backed live migration does not copy disks.

Ispconfig vs vestacp

This article will guide you on how to choose the best control panel for customers. Basically, many factors depends to choose the right panel like Ispconfig and Vestacp.

Vesta control panel (#VestaCP) is an open source hosting control panel, which can be used to manage multiple websites, create and manage email accounts, FTP accounts, and #MySQL databases, manage DNS records and more.


To Install And Use Vesta Control Panel:

1. Install SSH Client.

2. Choose The Configuration Panel.

3. Login to Putty and VestaCP Installation.

4. Create a new user.

5. Add a new domain and database.

6. Add Cloudflare nameservers.

7. Add files to your domain via FTP.

8. Repeat the process for all your websites.


ISPConfig is a free open-source control panel application that allows website owners to easily administer their sites, similar to cPanel and Plesk. 

It also allows resellers to manage multiple accounts on multiple physical or virtual servers.

ISPConfig only runs on #Linux servers.


To log into ISPConfig:

Navigate to the URL of your ISPConfig system (e.g. https://www.domain.tld:81 or http://www.domain.tld:81; replace "www. domain. tld" appropriately) with your Browser and enter your user name and your password into the form "Login". Confirm by clicking on "Login".

OpenLDAP and phpLDAPadmin on Linux

This article will guide you on how to install #OpenLDAP and phpLDAPadmin on #Ubuntu. Also, we covered the prospective error affacting OpenLDAP and phpLDAPadmin and its solution as well.

#LDAP (Lightweight Directory Access Protocol) is an open and cross platform protocol used for directory services authentication. LDAP provides the communication language that applications use to communicate with other directory services servers.

#Kerberos is used to manage credentials securely (authentication) while LDAP is used for holding authoritative information about the accounts, such as what they're allowed to access (authorization), the user's full name and uid.

To access #phpLDAPadmin:

Point your browser to http://IP_OF_SERVER/phpldapadmin (IP_OF_SERVER is the actual IP address of your LDAP server). 

From the main window, click the login button in the left pane. 

When prompted, you will log into your DN and enter the password for the admin user created during the slapd reconfiguration.

FFmpeg on CentOS

This article will guide you on how to install FFMPEG on #CentOS and fix its related #errors. FFmpeg is a powerful tool that can do almost anything with #multimedia files.

FFmpeg is a standard package on many #linux systems. 

You can check if it is installed with a #command like dpkg -s ffmpeg . 

If it is not installed, you should be able to install with your system's package manager. i.e. sudo apt-get install ffmpeg or search 'ffmpeg' in the Software Center on Ubuntu.

To run #FFmpeg in #Linux:

1. Start by updating the packages list: sudo apt update.

2. Next, install FFmpeg by typing the following command: sudo apt install ffmpeg.

3. To validate that the package is installed properly use the ffmpeg -version command which prints the FFmpeg version: ffmpeg -version. 

Install WireShark CentOS

This article will guide you on how to install WireShark on #CentOS. WireShark is one of the leading #network analyzing tools. It helps in troubleshooting the traffic problems of a server and malicious activity. 

Wireshark is an open-source, free network packet analyzer, used to capture and analyze network traffic in real-time.

Basically, with Wireshark you can capture and view data traveling through your network.

You can install WireShark with yum install wireshark-gnome . 

After you install it, the Wireshark application will be at /usr/sbin/wireshark .

To install #wireshark on RHEL 8 / CentOS 8 Linux step by step instructions:

1. Install package called Whireshark using the dnf command. For a GUI Wireshark application execute: # dnf install wireshark To install Wireshark command line tool only execute: # dnf install wireshark-cli.

2. Launch Wireshark.

To install Wireshark from #terminal:

Open terminal and type the #commands:

i. sudo apt-get install wireshark.

ii. sudo dpkg-reconfigure wireshark-common.

iii. sudo adduser $USER wireshark.

iv. wireshark.

Monitor System Metrics with the TICK Stack on CentOS 7

This article will guide you on how the TICK stack can be a powerful tool for storing, analyzing, and visualizing time series data. To monitor InfluxDB _internal metrics in a production #cluster, use Telegraf and the influxdb input plugin to capture these metrics from the InfluxDB /debug/vars endpoint and store them in an external InfluxDB monitoring instance.

More about Kapacitor:

#Kapacitor is a native data processing engine for #InfluxDB 1. x and is an integrated component in the InfluxDB 2.0 platform. 

Kapacitor can process both stream and batch data from InfluxDB, acting on this data in real-time via its programming language TICKscript.

A retention policy (RP) is the part of InfluxDB data structure that describes for how long InfluxDB keeps data. 

InfluxDB compares your local server's timestamp to the timestamps on your data and deletes data that are older than the RP's DURATION . 

A single database can have several RPs and RPs are unique per database.

Install XRDP Server

This article will guide you on steps to install XRDP #Server on #Ubuntu. To provide remote access via RDP, a Windows native protocol, XRDP behind the scenes uses #VNC, a remote access protocol more common in Linux.

After #xrdp is installed you can start the server with the following command:

Service xrdp start.

Service xrdp-sesman start (Thanks to Greg for pointing that out) — UPDATE!!

If want it to auto start after reboot you need to run this command also: update-rc.d xrdp enable (It will not start xrdp-sesman automatic).


To use XRDP Linux:

1. With #Ubuntu 18.04 first install xrdp: sudo apt-get -y install xrdp.

2. Next, one may adjust the configuration file: sudo nano /etc/xrdp/xrdp.ini.

3. Set encryption level to high: encrypt_level=high.

4. Next, allow just RDP through the local firewall: sudo ufw allow 3389/tcp.

Install Vesta control panel in Ubuntu

This article will guide you on easy steps to install Vesta control panel in #Ubuntu. VestaCP is a control panel for Linux with many features that facilitate the administration of a #server. 

Vesta Development team provides an installer script that automates setting up of Vesta hosting control panel on Ubuntu / Debian and RHEL based Linux distributions. Login to your Ubuntu / #Debian system and ensure the system is updated. Download #Vesta installer. Run install with sudo if you're logged in as standard user.

To install vestaCP on Ubuntu:

1. # Connect to your server as root via #SSH

ssh root@your.server

2. # Download installation script

curl -O http://vestacp.com/pub/vst-install.sh

3. # Run it

bash vst-install.sh

To change my VestaCP port:

i. conf file and change the port that NGINX listens on from 8083 to 2083 (or the port you chose to use). listen 2083; 

ii. Once the port has been changed, press CTRL+X , followed by y , and then hit enter to save your changes. 

iii. The final step is removing the firewall entry for the previous port we were using.

GlusterFS install CentOS 7

This article will guide you on the steps to install and setup #GlusterFS. 

GlusterFS is a scalable #network filesystem suitable for data-intensive tasks such as cloud storage and media streaming. 

GlusterFS has a client and #server component. Servers are typically deployed as storage bricks, with each server running a glusterfsd daemon to export a local file system as a #volume.

To install GlusterFS:

1. Have at least two nodes. CentOS 7 on two servers named "server1" and "server2".

2. Format and mount the bricks.

3. Installing GlusterFS.

4. #Iptables configuration.

5. Configure the trusted pool.

6. Set up a GlusterFS volume.

7. Testing the GlusterFS volume.

Enable firewalld in Centos 7 How to do it

This article will guide you on steps to enable firewalld on #centos 7 servers for our customers. The firewall is one of the most important features of webservers. The #firewalld supports both IPv4 and IPv6 #firewall #settings.

Never run the iptables service and FirewallD service at the same time! The #iptables service is now provided by a separate package called iptables-services: Stop and disable the firewalld service first. # systemctl stop firewalld.

The firewalld daemon manages groups of #rules using entities called "zones". Zones are basically sets of rules dictating what traffic should be allowed depending on the level of trust you have in the networks your #computer is connected to.

To use FirewallD:

1. Installing and Managing FirewallD.

2. To start the service and enable FirewallD on boot: sudo systemctl start firewalld sudo systemctl enable firewalld.

3. Check the firewall status.

4. To view the status of the FirewallD daemon: sudo systemctl status firewalld.

5. To reload a FirewallD configuration: sudo firewall-cmd --reload.

Imagick php install

This article will guide you on how to install #Imagick #PHP #extension. Imagick is the most popular PHP extension which helps to create edit convert, and/or manipulates images. ImageMagick is a free and open source, feature-rich, text-based and cross-platform image manipulation tool used to create, edit, compose, or convert bitmap images. It runs on #Linux, #Windows, #Mac Os X, iOS, Android OS, and many other operating systems.

To use Imagick with PHP in your server, you can easily achieve it with the following #command:

sudo apt-get install php-imagick.

php -m | grep imagick.

sudo service apache2 restart.

How Chmod 777 works

This article will guide you on how to give #Chmod 777 to folders and files in #Linux. We also discussed the risks and more information about file permissions. 

If you are managing a Linux system, it is crucial to know how the Linux #permissions work.

You should never set 777 (rwxrwxrwx) permissions #files and #directories permissions. 777 means that anyone can do anything with those files.

To Give Root Privileges to a User in Linux:

1. Adding to Root Group using usermod. Let see how we can grant normal user root access by adding to root group.

2. Adding to #Root Group using Useradd Command.

3. Editing /etc/passwd file.

4. Setting as Sudo User.

Ansible Playbook to Install WordPress with LAMP

This article will guide you on the step to follow to use #Ansible Playbook to install #WordPress with #LAMP on #Ubuntu 18.04.

In Ansible, the role is the primary mechanism for breaking a #playbook into multiple files. This simplifies writing complex #playbooks, and it makes them easier to reuse. The breaking of playbook allows you to logically break the playbook into reusable components.

To start using Ansible:

1. Prerequisites.

2. Install Ansible.

3. Establish a manual connection to a managed node.

4. Run your first network Ansible command.

5. Create and run your first network Ansible Playbook.

6. Gathering facts from network devices.

Install imagemagick on CentOS

This article will guide you on steps to #install #ImageMagick and fix its errors. Basically, ImageMagick is used to manipulate the digital images.

ImageMagick helps to create, edit, compose, or convert #bitmap images. It can read and write images in a variety of formats (over 200) including #PNG, JPEG, GIF, HEIC, TIFF, DPX, EXR, WebP, Postscript, PDF, and #SVG.

To install ImageMagick from the source:

1. First #download the latest version of the program sources - ImageMagick.

2. Unzip the package to a folder of choice.

3. In the folder where you have unzipped ImageMagick run the configuration script.

4. If no errors were found, you can start the install process.

Install Froxlor on CentOS 7

This article will guide you on steps to #install Froxlor on #CentOS 7 and also resolve common Froxlor #errors.
#Froxlor is a simple but powerful server administration #software for managing #domains, emails and files.
To install Froxlor web hosting control panel:
1. Ensure that your webserver serves /var/www.
2. Extract froxlor into /var/www.
3. Point your browser to http://[ip-of-webserver]/froxlor.
4. Follow the #installer.
5. Login as #administrator.
6. Adjust "System > Settings" according to your needs.
7. Choose your distribution under "System > Configuration".
8. Follow the steps for your services.

Yum http error 416 How to fix it

This article will guide you on steps to fix #yum #HTTP #error 416 which occurs while updating, installing, upgrading packages. This is rectified easily via disabling the delta #rpm problem, reinstalling a #package, clear #caching and so on.
To fix this error:
1. yum clean all
2. yum upgrade --exclude=polkit*
3. reboot
4. yum clean all
5. yum upgrade

Add Glance Cloud images to OpenStack

This article will guide you on steps to add #Glance #Cloud images to #OpenStack with different #Linux distributions which enables users to discover, register, and retrieve virtual machine images. 

After images are created they should be registered in Openstack Glance - #image operation service.

Upload Image Into Glance:

1. Replace <NAME> with the name that users will refer to the disk image by. 

2. Replace <IMAGE_FILE> with the local path to the image file to upload.

Cant locate LWP UserAgent pm in @INC

This article will guide you on how to get rid of error "Can't locate LWP/UserAgent.pm in @INC" which occurs in the process of installing #applications like CSF in the DirectAdmin server or any other #Linux #distros. 

libwww-perl (also known as LWP) is a collection of #Perl #modules that provide a simple and consistent programming interface (API) to the World-Wide Web.

In order to install and use this #package you will need Perl version

5.8.1 or better:

Some modules within this package depend on other packages that are distributed separately from Perl.  We recommend that you have the following #packages installed before you install

libwww-perl:

i. Digest-MD5

ii. Encode-Locale

iii. HTML-Form

iv. HTML-Parser

v. HTML-Tagset

vi. HTTP-Cookies

vii. HTTP-Date

viii. HTTP-Message

ix. HTTP-Negotiate

x. libnet

xi. LWP-MediaTypes

xii. MIME-Base64

xiii. Net-HTTP

xiv. URI

xv. WWW-RobotRules


If you want to access sites using the https protocol, then you need to

install the LWP::Protocol::https module from CPAN.

Install Graylog on CentOS 7 How to do it

This article will guide you on steps to #Graylog on #CentOS 7 and an effective method to make the logs more structured and searchable.

Graylog is a leading centralized log management solution built to open standards for capturing, storing, and enabling real-time analysis of terabytes of #machine data. 

Graylog is an open source log management platform which enables you to aggregate up to terabytes of log data, from multiple log sources, DCs, and geographies with the capability to scale horizontally in your data center, #cloud, or both.

To #Install Graylog 3 with Elasticsearch on CentOS 7:

1. Configure #SELinux. 

2. Add required #repositories 

3. Install #Java, #Elasticsearch, and #MongoDB. 

4. Configure Elasticsearch for Graylog. 

5. Install Graylog 3 on CentOS 7. 

6. Start Graylog service on CentOS 7.

Backup and Restore Nagios Log Server

This article will guide you on the steps to perform #backup and #restore a #Nagios #Log #Server cluster. Taking Backup and Restore of Nagios Log Server helps not to lose any data as it is held in other instances.

Backup and recovery describes the process of creating and storing copies of #data that can be used to protect organizations against data loss. #Recovery from a backup typically involves restoring the data to the original location, or to an alternate location where it can be used in place of the lost or damaged data.

To do a backup and system restore:

1. Click Start.

2. Go to Control Panel.

3. Go to System and Security.

4. Click Backup and Restore.

5. At the Back up or restore your files screen, click Restore my files. 

6. Browse to locate the backup file. 

Install InfluxDB on CentOS 7

This article will guide you on steps to Install #InfluxDB on #CentOS 7. You can Turn any InfluxData #instance into a production-ready cluster that can run anywhere. Easily create and share a comprehensive monitoring solution.

InfluxDB is similar to a #SQL #database, but different in many ways. Relational databases can handle time series data, but are not optimized for common time series workloads. InfluxDB is designed to #store large volumes of time series data and quickly perform real-time analysis on that data.

The local InfluxDB configuration file is located here: Linux: /etc/influxdb/influxdb. conf. macOS: /usr/local/etc/influxdb.

To Install InfluxDB:

Option 1 : Download the InfluxDB archive via the browser.

Option 2 : Adding the #repositories to your package manager.

i – Start your InfluxDB service.

ii – Configure your InfluxDB instance.

iii – Test your InfluxDB instance.

iv – #Download InfluxDB 2.0 archive from the website.

OpenLDAP on Ubuntu Steps to install it

This article will guide you on the steps to #install and configure #OpenLDAP on #Ubuntu.

OpenLDAP is a open source implementation of #LDAP in Linux.

If it's your #server, you will know just by looking at the running services. When you are there, run #netstat and probably you will see LDAP listening only on localhost . Remotely, if the server is listening on #localhost , you cannot know just by running nmap , the port will not answer for the public #interface.

To Install and Configure OpenLDAP on #CentOS / #RHEL #Linux:

1. Install OpenLDAP Packages. On CentOS and RedHat, use yum install as shown below, to install the openldap related packages. 

2. LDAP #Config Files. config. 

3. Create olcRootDN Account as Admin. 

4. Create olcRootPW Root Password. 

5. Create olcSuffix #Domain Name. 

6. Verify The #Configuration Files. 

7. Start the LDAP Server. 

8. Verify the LDAP Search.

How to Install OpenNMS on CentOS 8

This article will guide via a step-by-step procedure to #install OpenNMS in #CentOS. 

OpenNMS is a free, Open Source network monitoring system that can be used to #monitor tens of thousands of unlimited devices with a single #instance.

It will discover and monitor the services or nodes automatically in your #network, or you can assign a particular service to monitor by OpenNMS.

To configure #OpenNMS:

1. Install OpenNMS Horizon. Add yum repository and import GPG key. 

2. Initialize and set up #PostgreSQL. Initialization of the PostgreSQL database will start.

3. Initialize and start OpenNMS Horizon. 

4. First Login and change default password.

How To Install MariaDB on Ubuntu Focal Fossa

This article will guide you on steps to install #MariaDB from the #Ubuntu #repositories and from the official MariaDB repositories. You can install MariaDB in two different ways.

To install MariaDB on Ubuntu, follow these steps:

1. Update #packages index. sudo apt update.

2. Once the packages list is updated, install MariaDB by issuing the following command: sudo apt install mariadb-server.

3. The MariaDB service will start automatically.

The default data directory for the MariaDB database server is /var/lib/mysql. The configuration file of MariaDB database server is /etc/mysql/mariadb. conf. d/50-server.

SQL Server and create a database on Ubuntu How to install

This article will guide you on how to #install MS SQL on #Ubuntu Server 18.04. 

To Install #Microsoft SQL Server 2017:

1. Visit Microsoft's official SQL Server 2017 download page.

2. Select the edition you want to #download. 

3. Click Download now below your selected edition. 

4. The wizard will prompt you to select an installation type. 

5. On the next page, select a directory for the installation folder.

To connect to the SQL Server using #SSMS:

i. From the Connect menu under the Object Explorer, choose the #Database Engine.

ii. Then, enter the information for the Server name (localhost), Authentication (SQL Server Authentication), and password for the sa user.

iii. Click the Connect button to connect to the SQL Server.

oVirt Guest Agent on CentOS 8 and RHEL 8 Steps to install

This article will guide you on how to install oVirt Guest Agent on CentOS and RHEL. oVirt / #RedHat V#irtualization guest agent provides information, notifications, and actions between the #oVirt web interface and the guest.

To install oVirt guest agent:

1. Log in to the Red Hat Enterprise Linux virtual machine.

2. Enable the Red Hat Virtualization Agent #repository.

3. Install the guest #agent and #dependencies: # yum install ovirt-guest-agent-common.

4. Start and enable the ovirt-guest-agent service.

5. Start and enable the qemu-guest-agent service.

NFS Server on RHEL CentOS 8 Steps to install and configure

This article will guide you on the steps to Install and Configure #NFS Server on #RHEL or #CentOS.

The terms client and server are used to describe the roles that a computer plays when sharing file systems. The NFS service enables any given computer to access any other computer's file systems and, at the same time, to provide access to its own file systems.

To install NFS server:

1. Install NFS #Kernel Server. 

2. Create the #Export #Directory. 

3. Assign server access to client(s) through NFS export file. 

4. Export the shared directory. 

5. Open #firewall for the client (s).

VirtualHost cannot occur within virtualhost section in WAMP

This article will guide on steps to fix #VirtualHost cannot occur within virtualhost section in #WAMP which occurs while we try to add VirtualHost #directive and reconfigure #vhost.

Directory directive works only for filesystem objects (e.g. /var/www/mypage, C:\www\mypage), while Location directive works only for URLs (the part after your site #domain name, e.g. www.mypage.com/mylocation).

To Configure name-based virtual #hosts:

1. Install Apache webserver. Make sure you have installed #Apache webserver. 

2. Create web directory for each host. 

3. Create demo web pages for each host. 

4. Create configuration file for each host. 

5. Enable virtual host configuration files. 

6. Test Virtual hosts.

Manage a Linux Server with systemd

Like the init #daemon, #systemd is a daemon that manages other daemons, which, including systemd itself, are background #processes. systemd is the first daemon to start during booting and the last daemon to terminate during shutdown.

This article will guide you on how to manage #Linux server using systemd. Additionally, we saw the different commands used to Manage Linux serves with systemd. While systemd is compatible with SysV and Linux Standard Base (LSB) init scripts, systemd is meant to be a drop-in replacement for these older ways of getting a Linux system running.

To start (activate) a service , you will run the command 'systemctl start my_service. service', this will start the service immediately in the current session. 

To enable a service at boot , you will run 'systemctl enable my_service. service'.

Using Cron to Automate Tasks on CentOS 8

This article will guide you on the steps to set up #Cron job on #CentOS 8 to help automate #tasks. Cron is a #clock daemon, whose name originates from #Chronos, the Greek word for time. It enables users to automate the execution of #commands, scripts (a group of commands) or programs at specified time intervals.
The simplest way to validate that cron tried to run the #job is to simply check the appropriate log file; the log files however can be different from system to system. In order to determine which log file contains the cron #logs we can simply check the occurrence of the word cron in the log files within /var/log .

Deploy Laravel using Nginx on Ubuntu

This guide will help to set up Laravel with #Nginx on #Ubuntu 16.04. Laravel is the most popular, free, and open-source #PHP #framework in the world, known for its expressive and elegant syntax.
To move laravel project from localhost to production server, do:
1. Zip your #laravel app files.
2. Export your app's #database then set it up on your server.
3. After you have uploaded your laravel app files, open the . env file found on the root.
4. That's it!, now check your live #site.

How to install Metricbeat on CentOS 7 to Gather Infrastructure Metrics

This article will guide you on the steps to install #Metricbeat and configure the Elastic Stack to collect and analyze system metrics. Metricbeat is configured using a #YAML configuration file. On Linux, this file is located at: /etc/metricbeat/metricbeat. yml. On #Docker, you will find it at: /usr/share/metricbeat/metricbeat.
Both #Filebeat and #Logstash can be used to send #logs from a file-based data source to a supported output destination.

Steps To Harden OpenSSH Client on Ubuntu 18 04

This article will guide you on how to harden #OpenSSH Client by following some quick and easy steps.
#Hardening of the #OS is the act of configuring an OS securely, updating it, creating #rules and #policies to help govern the system in a secure manner, and removing unnecessary applications and services. This is done to minimize a computer OS's exposure to threats and to mitigate possible #risk.

HAProxy Logging with Rsyslog on CentOS 8

This article will guide you on how to set up #HAProxy Logging #Rsyslog with some quick and easy steps. HAProxy is installed with RightScale load #balancer ServerTemplates. Load-balancer servers are also known as front-end servers. Generally, their purpose is to direct users to available #application servers. HAProxy can be installed in front of them to provide load balancing and high availability.

Using Bpytop to monitor Linux and FreeBSD Resources

This article will guide you on how to use Bpytop Monitoring for Linux & FreeBSD Resources.

#Bpytop is a great utility which is useful on your #Linux, #macOS, and #FreeBSD as a #resource #monitor. It is much faster than bashtop and works pretty well as Python 3 is standard on many Unix boxes.

Steps to create a Self-Signed SSL Certificate for Apache in CentOS 8

This article will guide you on how to configure #Apache to serve encrypted requests using a self-signed SSL certificate and to redirect unencrypted HTTP requests to #HTTPS. Self-signed #certificates or certificates issued by a private CAs are not appropriate for use with the general public. It can only properly verify the identity of the server when it is signed by a trusted third party because any attacker can create a self-signed certificate and launch a man-in-the-middle attack.

Send NXLogs with SSL TLS to Nagios Log Server

This guide will guide you on how to send NXLogs with SSL/TLS to #Nagios #Log #Server. Encryption ensures that the traffic between the #Windows machine and Nagios Log Server is not sent in plain text.

Install and configure Grafana on CentOS 7

This article will guide you on the steps to #install #Grafana on #CentOS 7 which is a #visualization and #analytics #monitoring software. Grafana is Free and Open Source which Runs on all major #OS operating systems.

Step by step process to Secure Apache with Lets Encrypt on CentOS 8

This article will guide you on the process to secure #Apache with Let’s Encrypt by installing Let's Encrypt #Certbot client, downloading #SSL #certificates for the #domain, and setting up automatic certificate renewal.

The objective of Let's Encrypt and the #ACME protocol is to make it possible to set up an #HTTPS server and have it automatically obtain a browser-trusted certificate, without any human intervention.

YUM History command Ways to use it

This article will guide you on #YUM history #command in #Linux which provides a detailed history of YUM #transactions in order to find out information about installed packages and those that where removed/erased from a #system. 

The yum history command allows users to review information about a timeline of Yum transactions, the dates and times they occurred, the number of packages affected, whether transactions succeeded or were aborted, and if the RPM #database was changed between transactions.

How To Troubleshoot Common HAProxy Errors

This article will guide you on the different methods to #troubleshooting and fix common #HAProxy errors which can range from diagnosing #errors with the service itself to locating misconfigured options for modules. 

ifconfig centos 7

This article will guide you on the steps to #install #ifconfig in #CentOS using the yum #package #manager.

The ifconfig command can tell you a lot about your Unix server's connection to your #network and the role it's playing in both generating and receiving network traffic.

Install and Configure ModSecurity on Ubuntu

This article will guide you on the steps to perform #ModSecurity installation on #Ubuntu which involves enabling Core Rule Set to handle malicious activities.

NFS server not responding timed out error How to fix

This article will guide you on how to fix #NFS server not responding timed out #error which occurs when there is a heavy #server or #network load.

Why NFS is not working?

i. Check the file /proc/fs/nfs/exports and make sure the volume and client are listed correctly.

ii. Finally, try to ping the client from the server, and try to ping the server from the client. 

iii. If this doesn't work, or if there is packet loss, you may have lower-level network problems.

Install Prometheus Network Monitoring Server on CentOS 7

#Prometheus collects metrics from targets by scraping 3metrics #HTTP endpoints. Since Prometheus exposes #data in the same manner about itself, it can also scrape and monitor its own health. 

This article will guide you on the steps to perform #installation of Prometheus on #CentOS 7 along with the method used for the #setup.

Resizing the Nagios VM disk size for CentOS 7

This article will guide you on the process to resize the #Nagios #VM #disk size.

Sync Two CentOS 8 Servers Using File Replication

The #sync command forces an immediate write of all cached data to disk. Run sync if you anticipate the system to be unstable, or the storage device to become suddenly unavailable, and you want to ensure all data is written to disk. Individual files may be synced, or the entire filesystem containing the specified files.

This article will guide you on the right steps to sync two #CentOS 8 #servers using file replication.

Backup, Restore and Migrate a MongoDB database on CentOS 8

MongoDB is highly scalable, using shards. Horizontal scalability is a big plus in most #NoSQL databases. MongoDB is no exception. It is also highly reliable due to its replica sets, and the data is replicated in more nodes asynchronously.

This article will guide you on the steps to perform #backup, #restore and #migrate a #MongoDB #database on #CentOS 8.

Steps to Install Pure-FTPD on Ubuntu 18.04 LTS Server

#Pure-FTPd is a fast, production-quality, standard-conformant #FTP (SSL/TLS) server, based upon Troll-FTPd.

This article will guide you through the processes to install Pure-FTPd on your #Ubuntu server.

Zimbra Multi-Server Installation on CentOS 7

This article will help you to go about Installing a single server in Zimbra by following some steps.

Different methods to List Users in CentOS 7

This article will guide you on the different methods to list users in CentOS 7.

Virtualmin common installation errors

This article will guide you on the different common errors in Virtualmin / Webmin and their fixes.

Install Squid Proxy on CentOS 7

This guide will show you the steps to install squid on Centos 7 as well as configure the port and adjusting the access control list.

Install DHCP Server Client on Centos

This article will guide you on the steps to install and configure a DHCP server on CentOS 8.

Major effects of shifting focus to CentOS Stream

This article is about the major effects of shifting focus to the CentOS Stream which is a sudden move by Red Hat.

Install Kamailio SIP proxy server on CentOS 7 in a few steps

This article will guide you on the steps to install and configure Kamailio sip proxy on CentOS.

RM cannot remove read-only file system tips to fix

This article will guide you on how to fix 'rm cannot remove the read-only file system' error  by simply removing files from the read-only file system.

Install Nagios XI in an offline environment

This article will guide you on how to install Nagios XI in an offline environment using powershell.

TigerVNC Server installation and configuration

This article will guide you on how to install TigerVNC server CentOS 7.

Steps to Install Terraform On Ubuntu

This guide will show you how to install terraform on CentOS 7/Ubuntu 18.04.

Puppet installation on CentOS 7

This article will guide you through the steps you need to follow to get Puppet installed and configured on CentOS 7 Machine.

Htop installation on Linux


This article will show you how to install Htop across different Linux Distributions and Operating System.

Odoo installation on Centos

This article will guide you on how to install Odoo software on CentOS 7. Odoo is a very popular business software for managing business application.

Enable Epel repository on Linux

This article will show you how to enable EPEL repository on different Linux distribution. EPEL repo can be installed with the yum utility on CentOS and RHEL.

VirtualBox installation on CentOS 7

This article will help you to install VirtualBox on Centos. VirtualBox Software helps to create and run virtual machines on a single hardware machine.

Skyline installation on CentOS 7

The right steps to install Skyline and Redis databases.

How to Fix Boot Hole vulnerability CVE-2020-1073

Just recently, on the 29th, July 2020, Popular Linux Distribution RedHat announced that there was a great security concern in the grub2 (CVE-2020-1073) version.

Method to upgrade MySQL in VestaCP

It is very important to upgrade your OS MySQL database to the latest version so as to keep the system more secured and to enjoy the latest features.

Setup openvas on linux Debian and Ubuntu

OpenVAS software framework is a great security tool checking if the system is vulnerable by means of scanning and Management. It helps to safeguard the server from unauthorized access.


To Install OpenVAS on Ubuntu:

By default, the OpenVAS package is not available in the Ubuntu 16.04 repository, so you will need to add OpenVAS PPA to your system's repository list.

1. Add the OpenVAS PPA.

$ sudo add-apt-repository ppa:mrazavi/openvas

2. Update the repository.

$ sudo apt-get update

3. Finally, install OpenVAS.

$ sudo apt-get install openvas

4. Once OpenVAS has finished installing, start the OpenVAS service with the following commands:

$ sudo systemctl start openvas-scanner

$ sudo systemctl start openvas-manager

$ sudo systemctl start openvas-gsa

Restart Ubuntu 21.10 Impish Indri From the Terminal

This article covers some approaches to restart the Ubuntu system (Linux OS) like restarting Ubuntu using shutdown command, reboot command, init command, and systemd way. In fact, Every operating system needs to reboot or restart after some time due to various reasons. Some of the reasons are that certain software needs a reboot after installation to become fully functional, due to some configurational change, or maybe because of a software glitch. 

Check Kernel Version in Ubuntu 20.04 - Step by step guide ?

This article covers the different methods of finding the Linux Mint kernel version through various command line utilities. If you are interested in updating your kernel in Linux Mint 20, follow this guide: https://LinuxReels.com/resource/1332-update-linux-mint-20-3

Install Python on Linux Mint 20 - Step by step guide ?

This article covers how you can install Python 3.9 on your Linux Mint system. In fact, Python programming language can help in solving your programmatic problems.


Main features of Python includes:

  • It can be used on a server to create web applications.
  • It can be used alongside software to create workflows.
  • It can connect to database systems. It can also read and modify files.
  • It can be used to handle big data and perform complex mathematics.
  • It can be used for rapid prototyping or production-ready software development.

Change the Root Password in Linux Mint 20 - Step by step guide ?

This article covers the different method of changing the root password of a Linux Mint 20.3 system.

Install NGINX on openSUSE - Step by step guide ?

This article covers how you can easily install Nginx on your openSUSE system. In fact, Nginx or engine x is a high-performance HTTP- and proxy server with low memory consumption. It is used by large scale websites like Netflix, Pinterest, CloudFlare , Github etc. Nginx has an easy to learn configuration syntax and can act also as a load balancer with health checks and reverse proxy with caching features.


You can Install Nginx with the "zypper in" command:

$ zypper in nginx

Start nginx and enable it to be started at boot time:

$ systemctl start nginx
$ systemctl enable nginx

Install UNRAR on Fedora 35 / 34 / 33 / 32 - Step by step guide ?

This article covers how to install and use UNRAR freeware on Fedora. In fact, UNRAR is a great option for extracting RAR files and provides a myriad of options depending on how you want your files organized upon extraction. 

Install Steam on openSUSE - Step by step guide ?

This article covers how to install steam on openSUSE using different methods. In fact, Steam (https://www.steampowered.com) is a software content delivery system developed by Valve software (https://www.valvesoftware.com). 


How To Uninstall steam from Ubuntu 20.04 ?

To uninstall only the steam package we can use the following command:

$ sudo apt-get remove steam

We can use the following command to remove steam configurations, data and all of its dependencies, we can use the following command:

$ sudo apt-get -y autoremove --purge steam

Install Scala Compiler on Linux Mint 20.02 - Step by step guide ?

This article covers how to install the Scala compiler on your Linux Mint 20.02 machine. In fact, After installing this compiler, you will be all set to write codes using the Scala programming language. It includes modern language features such as closures, pattern-matching, parametric types, and virtual type members.

Different methods of Checking MySQL Version in Linux

This article covers the ways to check the MySQL version in Linux. In fact, MySQL (and its drop-in replacement MariaDB) is the most popular open-source relational database management system. There are some important differences between MySQL versions, so knowing which version is running on your server might be important in some situations.


How to Check MySQL Version with V Command ?

The easiest way to find the MySQL version is with the command:

$ mysql -V

The command mysql –V is not OS specific. This command works on Windows, OS X, and Linux distributions including Ubuntu.

Install VLC Media Player on Manjaro 21.2.2 Linux System

This article covers how to install VLC media player on Manjaro Linux. In fact, you can run the application whenever you want and stream videos on it. VLC supports subtitles, closed captions and is translated into numerous languages.

Most Effective GUI Tools to Free Up Space on Ubuntu and Linux Mint

This article covers the best GUI Tools to Free Up Space on Ubuntu and Linux Mint . In fact, you can use these tools to regularly keep your Ubuntu / Linux Mint system free of junk files.


How to Remove old kernels from the Ubuntu / Linux Mint system  ?

1. As we should know, the Linux Kernel is the heart of the system, but it is also known that it is updated every so often, so they are released new versions which are installed in the system displacing the old versions which remain stored without being eliminated.

For this we must type the following command:

$ sudo dpkg 'linux-image *' --list

2. Next, they must identify their oldest kernels and execute the following command to remove the previous versions.

Just replace xxxxx with the version of Linux you want to delete:

$ sudo apt-get remove linux-image-xxxxx

3. As an alternative, an easier way to clean up these old kernels is to use 'autoremove':

$ sudo apt-get autoremove  --purge

iostat Command in Linux - Explained with examples

This article covers how to use the iostat command in Linux. In fact, iostat command is used to monitor CPU utilization and I/O (input /output) statistics of all the disks and file systems. nfsiostat command is used to monitor i/o statistics of network file system(NFS).


iostat command generally generates two reports:

  • CPU utilization report.
  • All disks i/o statistics report.


To generate the reports, iostat command reads some of the system files . These files are:

  • /proc/diskstats for disk stats.
  • /proc/stat for system stats.
  • /sys for block device stats.
  • /proc/devices for persistent device names.
  • /proc/self/mountstats for all  the network filesystems.
  • /proc/uptime for information regarding system uptime.

Backup Your Data on Ubuntu 20.04 using Fwbackups - Step by step guide ?

This article covers how to install fwbackups and backup data in the application on Ubuntu 20.04. In fact, fwbackups is an open-source feature-rich user backup application that allows you to backup your important documents anytime, anywhere using a simple powerful interface with the support for scheduled backups and backing up to remote systems.


How to Install fwbackups on Debian and Ubuntu / Mint Linux ?

1. Install these following dependencies on your system:

$ sudo apt-get install gettext autotools-dev intltool python-crypto python-paramiko python-gtk2 python-glade2 python-notify cron

2. Then download fwbackups to your home directory using wget command and install it from source using the following commands:

$ wget http://downloads.diffingo.com/fwbackups/fwbackups-1.43.7.tar.bz2
$ tar xfj fwbackups-1.43.7.tar.bz2
$ cd fwbackups-1.43.7/
$ ./configure --prefix=/usr
$ make && sudo make install

3. Install fwbackups on CentOS and RHEL:

$ sudo yum install gettext autotools-dev intltool python-crypto python-paramiko python-gtk2 python-glade2 python-notify cron

4. Next, download fwbackups and install it from source using the following commands:

$ wget http://downloads.diffingo.com/fwbackups/fwbackups-1.43.7.tar.bz2
$ tar xfj fwbackups-1.43.7.tar.bz2
$ cd fwbackups-1.43.7/
$ ./configure --prefix=/usr
$ make && sudo make install

5. Install fwbackups on Fedora Linux:

$ sudo dnf install fwbackups


From the fwbackups Overview page, you can simply click on any one of the toolbar buttons to begin:

  • ⁠Backup Sets – To create, edit or delete backup sets as well as manually create a backup set.
  • ⁠One-Time Backup – Create "one-time" backups.
  • ⁠Log Viewer – Shows the information about fwbackups's activities.
  • Restore – Allows you to restore any backup from previously made backup.

How to install Bacula Server on Ubuntu Linux system ?

In order to install Bacula Server, log in to your Ubuntu instance and issue the command:

$ sudo apt-get install bacula -y

You will be prompted for the following:

  • Mail server configuration (unless you need email alerts, you can configure this as local only).
  • System mail name (this is the email domain for the server, if applicable).
  • Configure database for bacula-directory-pgsql (you want to do this and set it as localhost).
  • Configure a password for the Bacula PostgreSQL database.


Once you've completed the above, you'll get your prompt back and can continue on with the configuration.

Install Git on Rocky Linux 8 - Step by step guide ?

This article covers how to install and configure Git on Rocky Linux 8. In fact, Git is popular version control system designed to handle very large projects with speed and efficiency; it is used for many high profile open source projects, most notably the Linux kernel.


How To Uninstall git on Ubuntu 21.04 ?

To uninstall only the git package we can use the following command:

$ sudo apt-get remove git

We can use the following command to remove git configurations, data and all of its dependencies, we can use the following command:

$ sudo apt-get -y autoremove --purge git

Install Gitlab on Rocky Linux 8 - Step by step guide ?

This article covers how to install GitLab on Rocky Linux 8. In fact, GitLab is a free git repository management tool that allows you to create and manage git repositories. It provides tools for everything an open-source developer would need. Also it integrates perfectly with other development tools like CodeShip, which makes deployments easy and fast.

Enable PowerTools Repository on Rocky Linux 8 - How to do it ?

This article covers how to enable PowerTools repository on Rocky Linux and any other Red Hat Linux systems. In fact, The PowerTools repository is a container that contains many packages, libraries, and developer tools for either creating from source or installing applications. Most repositories rely on the PowerTools to be enabled, including the most popular Extra packages for the Enterprise Linux repository.


How to Install EPEL Repositories on Rocky Linux 8 ?

You need to enable EPEL since while installing a package being provided by the PowerTools repos, there might be some dependencies required and provided by the EPEL:

$ dnf install epel-release

Install Psensor Temperature Monitoring Application on Ubuntu 20.04 - Step by step guide ?

This article covers how to install the Psensor Temperature Monitoring Application on the Ubuntu machine through the command line and graphically.


psensor can monitor:

  • the temperature of the motherboard and CPU sensors (using lm-sensors).
  • the temperature of the NVidia GPUs (using XNVCtrl).
  • the temperature of the Hard Disk Drives (using hddtemp or atasmart lib).
  • the rotation speed of the fans (using lm-sensors).
  • the sensors of a remote computer (using psensor-server).


How to Install psensor Using apt on Ubuntu Linux system ?

Update apt database with apt using the following command:

$ sudo apt update

After updating apt database, We can install psensor using apt by running the following command:

$ sudo apt -y install psensor

Install Open Source osTicket on Ubuntu 20.04 - Step by Step guide ?

This article covers how to install the osTicket open source ticket system on Ubuntu 20.04 LTS Focal Fossa system. In fact, OsTicket allows you to manage, organize and archive your support request. It seamlessly routes inquiries created via email, web-forms, and phone calls into a simple, easy-to-use, multi-user, web-based customer support platform.


How to install osTicket with Nginx on Ubuntu ?

1. Update the system

First, log in to your server with sudo privileges and update the system with the latest stable version using the following command:

$ sudo apt update &&  sudo apt upgrade -y


2. Install LEMP Server

OsTicket requires Web server, PHP and Database Server to be installed on your server.

i. Install Nginx Web Server

You can install Nginx web server by the following command:

$ sudo apt install nginx -y

Now let's check Nginx service and To start the service manually, run the following commands:

$ sudo systemctl status nginx
$ sudo systemctl start nginx

Now enable nginx service to start at boot time by running the following command:

$ sudo systemctl enable nginx

ii. Install PHP and PHP-FPM

Next, you need to install PHP, PHP-FPM and some additional PHP modules which are required for OsTicket to run properly:

$ sudo apt install php php-mysql php-cgi php-fpm php-cli php-curl php-gd php-imap php-mbstring php-xml-util php-intl php-apcu php-common php-gettext php-bcmath

Above command will install php-7.2

Now edit php.ini file by running following command in terminal.

$ sudo vim /etc/php/7.2/fpm/php.ini

Uncomment cgi.fix_pathinfo variable and change its value to 0

cgi.fix_pathinfo=0

Now save and close the file.

Next, restart php7.2-fpm service and enable it at startup using the following command:

$ sudo systemctl restart php7.2-fpm
$ sudo systemctl enable php7.2-fpm

iii. Install and Configure MySQL Database server for OsTicket

From your terminal window, issue the following command to install the MySQL database server:

$ sudo apt install mysql-server

Now start MySQL service and enable it to start at boot time then check MySQL service status with the following command:-

$ sudo systemctl start mysql
$ sudo systemctl enable mysql
$ sudo systemctl status mysql

Next, secure MySQL installation with the following command:

$ sudo mysql_secure_installation

Answer all the questions as below:

Set root password? [Y/n] Y
New password:
Re-enter new password:
Remove anonymous users? [Y/n] Y
Disallow root login remotely? [Y/n] Y
Remove test database and access to it? [Y/n] Y
Reload privilege tables now? [Y/n] Y

Next, log in to MySQL console as shown below:

$ sudo mysql -u root -p

Enter your Root password here.

Now you need to create the database for osTicket

run following command:

$ mysql> create database osticket_db;
$ mysql> grant all privileges on osticket_db.* to osticket_user identified by 'OsTicketPassw0rd@19';
$ mysql> flush privileges;


3. Download and Configure osTicket

Create a new directory for osTicket and then go to that directory:

$ sudo mkdir -p /var/www/osticket/
$ cd /var/www/osticket/

Next download latest osTicket setup using wget and Extract it using the following command:-

$ sudo apt-get install wget unzip
$ sudo wget https://github.com/osTicket/osTicket/releases/download/v1.14.1/osTicket-v1.14.1.zip
$ sudo unzip osTicket-v1.14.1.zip

You will get scripts and upload directory after extracting.

Next create an osTicket configuration file from ost-sampleconfig.php file using the following command:

$ sudo su -
$ cd upload/
$ cp ost-sampleconfig.php ost-config.php

Next, you need to change ownership of the osTicket web directory to the 'www-data' user and group.

$ sudo chown -R www-data:www-data /var/www/osticket/


4. Create OsTicket Virtual Host

Now create new virtual host configuration for OsTicket by running following command:

$ sudo vim /etc/nginx/sites-available/osticket.conf

Paste the configuration as below:

server {
listen 80;
server_name 13.52.217.10;   ## change server_name as per your domain name.
root /var/www/osticket/upload;
access_log /var/log/nginx/access.log;
error_log /var/log/nginx/error.log;
index index.php index.html index.htm;

# Enable gzip
gzip on;
gzip_min_length 1000;
gzip_types text/plain application/x-javascript text/xml text/css application/xml;
set $path_info "";
location ~ /include {
deny all;
return 403;
}
if ($request_uri ~ "^/api(/[^\?]+)") {
set $path_info $1;
}
location ~ ^/api/(?:tickets|tasks).*$ {
try_files $uri $uri/ /api/http.php?$query_string;
}
if ($request_uri ~ "^/scp/.*\.php(/[^\?]+)") {
set $path_info $1;
}
location ~ ^/scp/ajax.php/.*$ {
try_files $uri $uri/ /scp/ajax.php?$query_string;
}
location / {
try_files $uri $uri/ index.php;
}
location ~ \.php$ {
fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
include fastcgi_params;
include snippets/fastcgi-php.conf;
fastcgi_pass unix:/run/php/php7.2-fpm.sock;
}
}

Here, You need to change server_name 13.52.217.10 as per your domain name.

Save the Nginx configuration file and exit.

Now activate the virtual host and test the configuration:

$ ln -s /etc/nginx/sites-available/osticket.conf /etc/nginx/sites-enabled/
$ nginx -t

Now restart nginx service:

$ sudo systemctl restart nginx


5. Install and configure osTicket

Now let's enter your domain name to get osTicket UI in any web browser.

Next Click on 'Continue' and you will be redirected to the osTicket configuration section.

Fill all required information and click “Install Now” button.

In the database settings, enter details as dbname, username, and password you have created during mysql setup.

Finally, Click on Install Now button

Next, change the permission of ost-config.php to remove write access by running the following command:

$ cd /var/www/osticket/upload/
$ chmod 0644 include/ost-config.php

For osTicket admin type your IP/domain name in the web browser.

For admin login/agent panel/Admin panel configuration type as following:

  • osTicket admin login - http://yourdomainname/scp/
  • osTicket agent panel - http://yourdomainname/scp/index.php
  • osTicket Admin panel configuration - http://yourdomainname/scp/settings.php

Install Rundeck on Ubuntu 20.04 - Step by step guide ?

This article covers how to install Rundeck on Ubuntu 20.04 for task automations in the system. In fact, Rundeck is a free open-source software for automation services. With Rundeck, you can create simple to complex tasks on either the local machine or on a remote server.

Install Grafana on CentOS 8 - Step by step guide ?

This article covers how to install and configure the Grafana monitoring tool on CentOS 8 system via the command line. In fact, Grafana is a popular open-source visualization and analytics monitoring software which renders graphs, charts, and alerts when connected to supported data sources. Now, you can use the grafana monitoring dashboard on CentOS 8 system.

Configure a Custom SSH Banner - Step by step guide ?

This article covers How to Set a Custom SSH Warning Banner and MOTD in Linux. In fact, SSH banner warnings are necessary when companies or organizations want to display a stern warning to discourage unauthorized parties from accessing a server.

Install Octave on Linux Mint 20 - Step by step guide ?

This article covers how to install the Octave programming language on a Linux Mint 20 machine. In fact, Octave is a (mostly MATLAB® compatible) high-level language, primarily intended for numerical computations. It provides a convenient command-line interface for solving linear and nonlinear problems numerically.


How to Install octave on Linux Mint via Snapd ?

1. Enable snapd

On Linux Mint 20, /etc/apt/preferences.d/nosnap.pref needs to be removed before Snap can be installed. This can be accomplished from the command line:

$ sudo rm /etc/apt/preferences.d/nosnap.pref
$ sudo apt update

To install snap from the Software Manager application, search for snapd and click Install.

Alternatively, snapd can be installed from the command line:

$ sudo apt update
$ sudo apt install snapd


2. Install octave

To install octave, simply use the following command:

$ sudo snap install octave

Install Suricata IDS on Ubuntu 20.04 - Step by step guide ?

This article covers how to install Suricata IDS on Ubuntu 20.04. In fact, Suricata is capable of real-time intrusion detection, intrusion prevention, and network security monitoring. For more information head over to the Suricata's documentation page.


Install PHP OPcache on Ubuntu 20.04 LTS - Step by step guide ?

This article covers the complete procedure for installing the PHP OPcache on your Ubuntu 20.04 LTS Focal Fossa system. In fact, OPcache is an Apache module for the PHP interpreter which is used to increase performance by storing precompiled scripts in shared memory space. It basically removes the need for PHP to load and parse scripts on each request.


How to Install and Configure PHP OPcache with Nginx ?

1. First, install the Nginx, PHP and other PHP extensions with the following command:

$ apt-get install nginx php php-fpm php-cli php-opcache php-mysql php-zip php-gd php-mbstring php-curl php-xml -y

2. Once all the packages are installed, verify the PHP version with the following command:

$ php -version

3. Next, you will need to enable the PHP OPcache by editing php.ini file.

$ nano /etc/php/7.4/fpm/php.ini

Uncomment the following lines:

opcache.enable=1
opcache.memory_consumption=128
opcache.max_accelerated_files=10000
opcache.revalidate_freq=200

Next, Save and close the file then restart Apache service to apply the changes:

$ systemctl restart nginx php7.4-fpm

4. You can now verify the PHP OPcache installation with the following command:

$ php -i | grep opcache

Install FTP Server on Linux Mint 20 - Step by step guide ?

This article covers the complete procedure to install and configure the latest version of the FTP Server on the Linux Mint system. In fact, VSFTP (very secure FTP) is a secure FTP protocol which encrypts information transfer between systems.

To Install VSFTPD on Linux Mint 20, Simply Run the following commands to install VSFTP server on Linux Mint 20:

$ sudo apt-get update
$ sudo apt install -y vsftpd

Install FreeIPA on CentOS 8 - Step by step guide ?

This article covers how to install the FreeIPA on CentOS 8 system. In fact, FreeIPA is a free and open source identity management tool for managing centralized authentication along with account management, policy (host-based access control) and audit.


How to Open Required FreeIPA ports on Firewall ?

FreeIPA uses a number of ports to communicate with its services which must be opened on firewall to allow external connections. You can simply open all the required ports using the service names by running the command below:

$ firewall-cmd --add-service={freeipa-ldap,freeipa-ldaps,dns,ntp} --permanent
$ firewall-cmd --reload

Install LibreNMS on Ubuntu 20.04 LTS using Nginx - Step by step guide ?

This article covers the process of installing LibreNMS on your Ubuntu 20.04 LTS Focal Fossa system. In fact, LibreNms works and supports protocols such as SNMP, LLDP, OSPF, ARP, CDP, BGP and FDP to auto-discover the network.  You can also use LibreNms to monitor many network hardware (such as Cisco, Juniper, Foundry, FreeBSD, Brocade) and even operating systems such as Windows, Linux, and FreeBSD.

Install / Enable RPM Fusion on Rocky Linux 8 - Step by step guide ?

This article covers how to install RPM fusion on AlmaLinux 8 / Rocky Linux 8. In fact, RPM Fusion is a repository specifically for Fedora Linux which is an amalgamation of the software repositories Livna, Freshrpms, and Dribble to bundle resources. 


How to Disable or Enable any repository like RPM Fusion from Rocky Linux 8 system ?

1. Install Yum Utils:

$ sudo dnf install yum-utils

2. Command syntax to enable or disable repo:

$ sudo yum-config-manager --disable repository-ID

3. To get the ID list the repositories using:

$ dnf repolist

Let's say we want to disable Fusion then the command will be:

$ sudo yum-config-manager --disable rpmfusion-free-updates

To enable the same in the future, use:

$ sudo yum-config-manager --enable rpmfusion-free-updates

4. To List, all the enabled and disabled repositories simply type:

$ dnn repolist all

Install nload to Monitor Real Time Network Traffic on Ubuntu 20.04 Linux system - Step by step guide ?

This article covers the different ways to easily install nload on your Ubuntu system. In fact, nload is a command-line utility that can be used to monitor network traffic and bandwidth usage in real time. It visualizes the in-comming and out-going traffic using two graphs and also provides additional information like min/max network usage and total transferred data. 

Install and Use Neofetch on Linux ( RHEL /CentOS / Arch ) - Step by step Guide ?

This article covers different ways of installing Neofetch on major Linux distributions. In fact, Neofetch is a handy tool when you want to display information about the system you are working on. It's mostly useful in tutorials and guides when you want to show your readers the OS and hardware type you are using.

To see what other options you can specify with Neofetch, run the neofetch --help command.

Install WildFly on Ubuntu 20.04 - Step by step guide ?

This article covers how to successfully install and configure WildFly on Ubuntu 20.04. Infact, WildFly offers you an administration dashboard to manage single or multiple domains efficiently.

Disable the Firewall on Linux Mint 20 - Step by step guide ?

This article covers the different ways of disabling the Firewall on a Linux Mint 20 system. In fact, You can easily disable the Firewall for Linux via the following tools:

  • ufw – Used by Ubuntu and Debian based system to manage the firewall.
  • firewalld – Used by RHEL, CentOS and clones. It is a dynamic solution to manage the firewall.

Migrate from CentOS 7.x versions to RHEL 8.x using Elevate Project

This article covers the complete process of migrating from CentOS 7.x to AlmaLinux using the Elevate upgrade packages. In fact, You can upgrade to other RHEL 8.x distros using different leapp migration data packages.

Install ProFTPD on Linux Mint 20 - Step by step guide ?

This article covers how you can instantly install ProFTPD on a Linux Mint 20 system. In fact, ProFTPD will easily facilitate transferring your files from one end to another while fully supporting the file transfer protocol.

Install Kubelet on Linux Mint 20 - Step by step guide ?

This article covers how to install Kubelet on a Linux Mint 20 system via the Snap Store. In fact, With the help of this amazing technology, we can easily manage the Kubernetes nodes. 

Install Terminator on Linux Mint 20 - Step by step guide ?

This article covers the installation method of Terminator on Linux Mint 20. In fact, a Linux terminal environment enables a user to carry out various system functionalities like file management, system update, and applications management through a variety of executable commands.


Main features of Terminator Terminal includes:

  • Multiple plugins support.
  • Simultaneous typing especially when dealing with arbitrarily grouped terminals.
  • Access to numerous keyboard shortcuts.
  • Multiple profiles and layouts support which, through GUI preferences editor, can be saved.
  • Terminals re-ordering through drag-and-drop.
  • Multiple tabs support.
  • Support for grid-like structure terminal arrangement.

Install 7-zip on Ubuntu 20.04 - Step by step guide ?

This article covers how to install 7-zip on Ubuntu 20.04 LTS Focal Fossa system. In fact, 7-Zip is an archive format that is widely used and gives a high compression rate.


How to Use 7Zip in Ubuntu Linux system ?

If you are on Ubuntu run the following commands:

$ sudo add-apt-repository universe
$ sudo apt update

After you have updated all your repositories run the following command to install 7Zip:

$ sudo apt install p7zip-full p7zip-rar

Install Tesseract on Linux Mint 20 - Step by step guide ?

This article covers the installation procedure of Tesseract OCR on a Linux Mint 20 system. In fact, Tesseract is an optical text recognition (OCR) engine developed by Google used for recognizing a text in image. 


How to Install Tesseract OCR on Ubuntu ?

1. Add the Tesseract OCR repository:

$ sudo add-apt-repository -y ppa:alex-p/tesseract-ocr-devel

2. Install Tesseract OCR 5:

$ sudo apt install -y tesseract-ocr

3. When installation is finished, we can check Tesseract OCR version:

$ tesseract --version


How to Uninstall Tesseract OCR from Ubuntu Linux system ?

If you decided to completely remove Tesseract OCR and related dependencies, run the following command:

$ sudo apt purge --autoremove -y tesseract-ocr

2. Remove GPG key and repository:

$ sudo rm -rf /etc/apt/trusted.gpg.d/alex-p_ubuntu_tesseract-ocr-devel.gpg
$ sudo rm -rf /etc/apt/sources.list.d/alex-p-ubuntu-tesseract-ocr-devel-focal.list

Install WordPress on Rocky Linux 8 using the LAMP stack - Step by step guide ?

This article covers how to install WordPress on Rocky Linux 8. In fact, WordPress  is open-source, written in PHP and use a MariaDB/MySQL as a database backend. WordPress is the most popular content management system used to host static and dynamic websites on the Internet. You are now ready to create your blog or website.

Install Bpytop Resource Monitoring Tool on CentOS 8 - Step by step guide ?

This article covers how to install Bpytop on the CentOS system. In fact, Bpytop provides a command-line interface to monitor system resources including disk, network, process, and CPU in real-time. Bpytop can be installed on several operating systems including Linux, macOS, and FreeBSD. Now you can start using it to monitor your system's resource usage.


How to Install bpytop on your Linux system ?

1. The best way to install the bpytop is by typing the following command to install or upgrade to the latest version:

$ pip3 install bpytop --upgrade

2. On Arch Linux install bytop, Run the pacman commands:

$ sudo pacman -Syu
$ sudo pacman -S bpytop

3. On Debian 11, We use the apt command:

$ sudo sh -c 'apt update && apt -y upgrade && apt -y install bpytop'

4. For RHEL 8 enable EPEL (see how to enable and use EPEL on CentOS 8) and then type the dnf command:

$ sudo sh -c 'dnf update && dnf install bpytop'

5. On FreeBSD install bpytop, Run the pkg command to install bpytop:

$ sudo pkg install bpytop

6. On Ubuntu snap installation, Execute the following snap command:

$ sudo snap install bpytop

Install GoAccess on Ubuntu 20.04 LTS - Step by step guide ?

This article covers the process of installing the GoAccess real-time web log analyzer on Ubuntu 20.04 LTS Focal Fossa system. In fact, GoAccess is a free and open-source weblog analyzer tool used for the analysis of logs in real-time. You can analyze logs through a web browser or terminal. 

GoAccess provides very useful statistics to system administrators including, top visitors, bandwidth, referring sites and URLs, operating systems, IP location, reverse DNS, geolocation, HTTP status code, and much more.

Install Percona Database Server on Ubuntu 20.04 - Step by step guide ?

This article covers the process of installing Percona Database Server on Ubuntu 20.04. In fact, Percona Server is fully compatible and a replacement for Oracle MySQL. Percona Server is used by thousands of enterprises to provide superior performance, scalability, and instrumentation for their workloads.

Install Rar / Unrar on Centos 8 - Step by step guide ?

This article covers how to install Rar/Unrar on CentOS 8 system. In fact, RAR files are archived by Winrar compression software and can be split into large files.

Install Screen on Linux Mint 20 - Step by step guide ?

This article covers how to install the Screen tool on your Linux Mint 20 system. In fact, Linux Mint screen provides users an option to open several separate terminal instances within a single terminal window manager. Screen also includes an enhanced command line, giving you extra features and functionality over a standard command line.


How to Install and Use Linux Screen ?

Screen is usually installed by default on all major Linux distributions. If your system doesn't have it preinstalled, don’t worry, the installation process is easy.

1. In the case of Debian, Ubuntu or Linux Mint and its derivatives, you can execute the following command:

$ sudo apt install screen

2. If you are using CentOS, you can install it using the following:

$ sudo yum install screen

Or if the user can't run sudo commands, we need to run it as a root user:

$ yum install screen


How to install htop on your Linux system ?

We can install it on Debian, Ubuntu, Linux Mint and its derivatives with the following command:

$ sudo apt install htop

You can run htop by simply typing the following command in your terminal:

$ htop

Install and Configure Nessus Vulnerability Scanner on CentOS 8

This article covers how to install and configure Nessus vulnerability scanner on the CentOS system. Now you can start running scans on your systems to find any vulnerability that can be exploited by attackers. 


How to start Nessus on CentOS 8 ?

Now run the following commands to start the Nessus service, enable that server at startup and check Nessus service status by running the following command:

$ sudo systemctl start nessusd.service
$ sudo systemctl enable nessusd.service
$ sudo systemctl status nessusd.service

At this time Nessus service running on default port 8834 successfully, Before you start post-installation, you need to open up that port in your firewall. To do so run the following command:

$ firewall-cmd --zone=public --add-port=8834/tcp --permanent
$ firewall-cmd --reload

Now go to your browser and enter your server name or IP along with the default port of Nessus:

https://server_name_or_ip:8834/

Install FreeIPA on Ubuntu 20.04 LTS - Step by step guide ?

This article covers the process of installing FreeIPA open source identity management system on your Ubuntu 20.04 LTS Focal Fossa. In fact, FreeIPA is free and open source Identity, Policy, and Audit (IPA) suite sponsored by RedHat. It's an IPA solution combination of Linux (Fedora), 389 Directory Server, MIT Kerberos, NTP, DNS Bind, Dogtag, Apache web server, and Python.

Install ClamAV on CentOS 8 - Step by step guide ?

This article covers the process of installing ClamAV antivirus on CentOS 8 system. In fact, ClamAV is an open source (GPL) antivirus engine designed for detecting Trojans, viruses, malware and other malicious threats on Linux.

Install Apache Ant on CentOS 8 - Step by step guide ?

This article covers the process of installing Apache Ant on your CentOS 8 system. In fact, Apache Ant is a Java library and command-line tool that help building software. Ant supplies a number of built-in tasks that allows to compile, assemble, and run Java applications. Its build files are written in XML so it is open standard, portable and easy to understand.

Install Apache Ant on Ubuntu 20.04 LTS - Step by step guide ?

This article covers the process of installing Apache Ant on your Ubuntu 20.04 LTS Focal Fossa system. In fact, Apache Ant is a software tool for automating software build processes especially on Java environments. It is a Java library and command-line tool whose mission is to drive processes described in build files as targets and extension points dependent upon each other. The main known usage of Ant is the build of Java applications.

Install HAProxy on CentOS 8 - Step by step guide ?

This article covers the process of installing HAProxy on your CentOS 8 systems. In fact, HAProxy is an open-source software widely used as a high availability load balancer and proxying TCP and HTTP connections.

Install Steam on CentOS 8 - Step by step guide ?

This article covers the process of installing Steam on your CentOS 8 system. In fact, Steam is a very popular and widely used online gaming library among the gaming community. It provides thousands of games to play and lets you communicate with online players. It is available on many platforms and can be used in Linux as well.


How to Install Steam Using the Flatpak ?

1. Make sure that the epel repository is enabled on your CentOS 8:

$ sudo dnf install epel-release

2. And also, verify that system's repository is up to date by typing the command given below:

$ sudo dnf update

3. Make sure that Flatpak is installed on your CentOS 8 machine. It comes pre-installed on CentOS 8 and you can verify its installation by typing the below command:

$ flatpak --version

4. If Flatpak is not installed on your CentOS 8 system due to any reason, install it using the command below:

$ sudo dnf install flatpak

5. After installing Flatpak, type the command given below to add the flathub repository to your CentOS 8 system as well:

$ flatpak remote-add --if-not-exists flathub https://flathub.org/repo/flathub.flatpakrepo

6. You can install Steam on your CentOS 8 system by typing the command given below:

$ flatpak install flathub com.valvesoftware.Steam -y

The "-y" flag will automatically say yes whenever a prompt will occur to confirm the installation.

Install Icinga on Ubuntu 20.04 LTS - step by step process ?

This article covers the process of installing Icinga 2 on your Ubuntu LTS system. Infact, Icinga is a computer system and network monitoring application that checks the availability of your network and computer resources, notifies system outages, generates performance data of your resources, and provides the high-availability and distributed monitoring setup with the built-in cluster feature. 

Install Dokuwiki on Ubuntu 20.04 LTS

This article covers the process of installing Dokuwiki on your Ubuntu 20.04 LTS Focal Fossa system. In fact, DokuWiki is an open source wiki program written in PHP that doesn't require a database. It stores data in text files.

Install Chromium on CentOS 8 - A step by step guide ?

This article covers the process of installing the Chromium web browser in CentOS 8 system. In fact, The Chromium project covers two utilities such as Chromium and Chromium OS, which are the open source projects of the Google Chrome browser and Google Chrome OS. Chromium has been developed as an open-source browser project whose critical mission is to offer a more secure, faster and more stable way to navigate the web where threats are constant at every minute.

Install Vivaldi Browser on CentOS 8 - A step by step guide ?

This article covers the process of installing Vivaldi Web Browser on CentOS 8 systems. In fact, Vivaldi web browser is created for speed, privacy and secure browsing experience by blocking ads and trackers.

Install Transmission on CentOS 8 - A step by step guide ?

This article covers the complete process of installing Transmission BitTorrent Client on CentOS 8 system. In fact, Transmission is a good lightweight bittorrent Downloader for Downloading Torrents Files.

Install Mattermost on CentOS 8 - A step by step guide ?

This article covers the process of installing Mattermost on CentOS 8 system. In fact, Mattermost is an open source, self-hosted team chat and collaboration software.

Install Puppet on Ubuntu 20.04 LTS - A step by step guide ?

This article covers the process of installing the Puppet on 20.04 LTS Focal Fossa system. In fact, Puppet is a free and open-source automated administrative engine for Linux, Unix, and Windows operating systems. It is used for deploying, configuring, and managing servers and performs administrative tasks such as adding users, installing packages, and many more.

Furthermore, It helps system admins to free up time and mental space by automating tasks on thousands of physical and virtual machines. It uses a client-server model. Where Puppet master controls configuration information for Puppet agents while Puppet agents talk to and pull down configuration profiles from the Puppet master.

For additional help or useful information, we recommend you to check the official Puppet website.

Set Up DHCP Server on CentOS 8 - How to do it ?

This article covers the process of installing DHCP Server on CentOS 7 system. In fact, Dynamic Host Configuration Protocol (DHCP) is a communication protocol that computers use to automatically assign IP addresses to devices connected to a local network or over the internet. 

Install Cacti Monitoring on Debian 10 - A step by step guide ?

This article covers the process of installing Cacti Monitoring on Debian 10 Buster system. In fact, Cacti is a free and open-source, web-based network monitoring, and graphics tool which provides a fast poller with advanced graphic template creation and multiple data collection methods. 

For additional help or useful information, we recommend you check the official Cacti Monitoring website.

Install Microsoft SQL Server on CentOS 8 - A step by step guide ?

This article covers the process of installing Microsoft SQL Server (MS SQL) on your CentOS 8 system. In fact, SQL Server is Microsoft's proprietary relational database management software. It supports various operating systems and installation methods, including Linux distributions like Ubuntu, Red Hat, and CentOS.

For additional help or useful information, we recommend you to check the official Microsoft SQL Server website.

Install Vtiger CRM on CentOS 8 - A step by step guide ?

This article covers how to install and configure Vtiger CRM on a CentOS 8 system. In fact, vTiger CRM is a web-based, modular and complete Open Source full-fledged customer relationship management system for sales force automation, customer support & service, marketing automation, procurement & fulfillment effectively. It is basically a native thin-client, browser-based application built on the LAMP/WAMP (Linux/Windows, Apache, MySQL and PHP) stack.

Install PHP Composer on CentOS 8 - Step by step Process ?

This article covers the installation procedure of PHP composer on your CentOS 8 system. In fact, Composer is a dependency manager for PHP, it like npm for Node.js or pip to Python. So, it allows you to declare the libraries your project depends on and it will manage (installing/updating) them for you. It is used in all modern PHP frameworks and platforms such as Laravel, Symfony, Drupal, and Magento 2.

Install Snap on Linux Mint 20 - A step by step Process ?

This article covers how to install snap on Linux Mint 20. In fact, Snaps are 'universal' packages that work across many different Linux systems, enabling secure distribution of the latest apps and utilities for cloud, servers, desktops and the internet of things.

Install Python 3.10 on Rocky 8 - A step by step process ?

This article covers the process of installing Python 3.10 on Rocky Linux 8. In fact, Python is one of the most popular high-level languages, focusing on high-level and object-oriented applications from simple scrips to complex machine learning algorithms.


Install and Configure CSF(Config Server Firewall) on Ubuntu 20.04 LTS

This article covers the process of installing Config Server Firewall on Ubuntu 20.04. In fact, Config Server Firewall (CSF) is a popular security tool for Linux comes with multiple features such as stateful packet inspection firewall (SPI), intrusion detection, a login failure daemon, DDOS protection, and control panel integration.

For additional help or useful information, we recommend you check the official CSF website .

Install Strace on Linux Mint 20 - Step by step process ?

This article covers how you can install and use Strace very conveniently on your Linux Mint 20 system. In fact, Strace is a very powerful Troubleshooting tool for tracing system calls.

Install PHP 7.4 on CentOS 8

This article covers how to install PHP on CentOS 8. You will also see how to change the default PHP version to the latest available version. After installing the PHP on your system, you can configure it with an Apache webserver or Nginx. 

PHP (PHP: Hypertext Preprocessor) is a server-side scripting language designed for web development but also used as a general-purpose programming language. PHP code is interpreted by a web server with a PHP processor module, which generates the resulting web page: PHP commands can be embedded directly into an HTML source document rather than calling an external file to process data.

Install Netdata on Linux Mint 20

This article covers how to install Netdata on a Linux Mint 20 machine and then use this service for measuring the performance of your system. In fact, Netdata is a free and open-source real-time monitoring and troubleshooting tool for cloud servers, containers, applications, and on-premise IT infrastructure. You can view the results in a highly interactive web-dashboard.

Install MyPaint on Ubuntu 20.04 LTS

This article covers how to install, launch, and remove MyPaint on Ubuntu 20.04 LTS. In fact, MyPaint an open-source, fast painting program that centers around full-screen use, with the idea that the user should focus on the art rather than the interface.


How to install or uninstall mypaint on Ubuntu 20.04 LTS (Focal Fossa)?

1. To install mypaint package, run the below commands:

$ sudo apt update
$ sudo apt install mypaint


2. To Uninstall mypaint package, execute the commands:

$ sudo apt remove mypaint
$ sudo apt autoclean && sudo apt autoremove

Install Tor browser on Rocky Linux / AlmaLinux 8

This article covers how to install the latest Tor Browser on Rocky Linux 8. In fact, Tor, also known as The Onion Router, is open-source, free software that enables anonymous communication when using online services such as web surfing. The Tor network directs the Internet traffic through an accessible worldwide volunteer overlay network with over six thousand relays and continues to grow. Many users want to find more ways to keep their information and activities anonymous or at least as private as possible, which has led to Tor Browser growing quite popular in recent years as it conceals a user's location and usage from anyone conducting network surveillance or traffic analysis.


Install Grafana on Rocky Linux 8

This article covers how you can add data sources from a myriad of environments and start monitoring your applications with Grafana on your Rocky Linux 8 system. In fact, Grafana is the open source analytics and monitoring solution that enables you to query, visualize and alert on various systems metrics that can be pulled from various time series databases such as Graphite, InfluxDB & Prometheus etc.

Create a Backup ISO File using Mkisofs in Linux Mint 20

This article covers how you can create a backup ISO file in Linux Mint 20 using Mkisofs. After installing this tool on your system, you can create backups of any desired files very conveniently.

The basic syntax of Mkisofs command is: $ mkisofs -o [filename.iso] [ directory_path]

Install Docker on Debian 11 bullseye system

This article covers how to install Docker engine on the Debian 11 bullseye system. In fact, Docker is a toolset to build applications and CI/CD pipelines to build, ship and run your applications in containers.

Install Grsync on Debian 10 Linux system

This article covers how to install and remove Grsync from Debian 10 Linux system. In fact, Grsync is a Graphical rsync backup tool for Linux systems. It basically provides a graphical user interface to backup or sync important files & directories to remote machines or in local machines using rsync.


How to Install Grsync on Debian ?

Open the Terminal, run the below apt-get command:

$ sudo apt-get install grsync

Install Jenkins on CentOS 8

This article covers how to install Jenkins on CentOS system. In fact, Jenkins is an open-source software written in Java and Scala which allows users the ability to automate almost any task and, it saves significant time that can be better utilized addressing other issues. When automating tasks with Jenkins, users can optimize their workflow by quickly automating the jobs that servers cannot do themselves.

Also, you will learn how to manage Jenkins services, allow them in firewall, and access Jenkins using the web browser.

Install Ntopng on Ubuntu 20.04 LTS

This article covers how to install ntopng on Ubuntu OS and access its web interface. In fact, Ntopng is an essential application for monitoring and troubleshooting network problems.


More about Ntopng

Ntopng basically is a network traffic probe that will monitor network usage. It is based on libpcap, a Library written as part of a larger program called TCPDump. Ntopng is based on Redis key value server rather than traditional database, leverages nDPI for protocol discovery, supports host geolocation, and can display real-time flow analysis for connected hosts.


Main Features of Ntopng:

  • Packet capture → Packet capture / transmission using basic hardware with PF_RING. Zero-copy package distribution across threads, applications, and virtual machines. Includes Libpcap support for seamless integration with legacy applications.
  • Traffic recording → Lossless network traffic recording of 10 Gbit and above with n2disk. Industry standard PCAP file format. It allows to quickly retrieve packages using BPF. Accurate traffic reproduction with disk2n.
  • Network probe → nProbe- NetFlow v5 / v9 / IPFIX extensible probe with plug-in support for L7 content inspection.
  • Report on the use of the IP protocol → Even going so far as to classify it by type of protocol.
  • Traffic analysis → High speed web based traffic analysis and flow collection using ntopng. Persistent traffic statistics in RRD format. Layer 7 analysis leveraging nDPI, an open source DPI framework. Even going so far as to classify the traffic according to the source / destination.
  • Geolocate and Overlay Hosts → This will be done on a geographic map.
  • Alert engine → We can capture anomalous and suspicious hosts.
  • Produce network traffic statistics → Using HTML5 / AJAX technology.
  • We will have full support for current network protocols → Including IPv4 and IPv6.

Install Anaconda on CentOS 8

This article covers how you install Anaconda on your CentOS system. In fact, Anaconda manages many pre installed packages and that packages are helpful for data science, Machine Learning and Artificial intelligence applications. Once installed on your system, you can now start building your machine learning projects.

Install Elinks on Ubuntu 20.04

This article covers how to install, run, and remove Elinks browser on Ubuntu 20.04 LTS. In fact, Elinks runs in the terminal. Not only it saves bandwidth but also consumes a few system resources. On a server where resources are always constrained, elinks can be the best choice to access the web.


Step by step installation of elinks:

1: Update system:

$ sudo apt-get update

2: Install: elinks

Ater updating the OS run following command to install the package:

$ sudo apt-get install elinks


How to Completely remove elinks with all configuration files from Ubuntu?

Following command should be used with care as it deletes all the configuration files and data:

$ sudo apt-get purge elinks

or you can use following command also:

$ sudo apt-get purge --auto-remove elinks

Above command will remove all the configuration files and data associated with elinks package. You can can't recover the delete data, so, use this command with care.

Install MiddleMan on Ubuntu 20.04

This article covers the installation of ruby, middleman, and related gems on Ubuntu 20.04 LTS Linux system. In fact, Middleman is a Ruby-powered static site generator which follows an easy-first approach to building static sites. It has powerful features for maintaining static blogs, like easy tag generation, quick commands for listing categorized articles and pagination.

You can install Middleman with Ruby using this command:

$ gem install middleman

Install NetHogs on Linux Mint 20 - Follow these steps ?

This article covers how to install the NetHogs network bandwidth monitoring utility very easily on your Linux Mint 20 system. In fact, you will be able to get the network bandwidth usage in real-time very efficiently without any sort of hassle.

Install phpMyAdmin on AlmaLinux / CentOS 8 - Follow the steps outlined here ?

This article covers the installation and configuration procedure of phpMyAdmin on CentOS 8 / AlmaLinux 8. It is one of the most popular database administration tools used by hosting companies and system administrators for performing database activities such as creating, deleting, querying tables, columns, relations, indexes, users, permissions, etc. Now, you can create and manage all the databases conveniently without the need of running SQL queries.

Install Stacer on Linux Mint 20 - A step by step guide ?

This article covers the best procedure of Installing Stacer on Linux Mint 20. In fact, Stacer is an amazing tool for Linux system monitoring and optimizing. It is a multi utility tool with features that allows you to easily manager your Linux system. Once installed successfully, Stacer can easily be used for system monitoring and improving its performance and efficiency.


How to Install Stacer on Linux ?

If you want the latest version of Stacer then open a new Terminal Window and execute the following command line by line:

$ sudo add-apt-repository ppa:oguzhaninan/stacer
$ sudo apt update
$ sudo apt install stacer

This will add Stacer PPA in your repository and install the latest version of Stacer on your system.

However, if you want to install the most stable release (tested) of stacer, which can be installed from the official repository of your operating system then open terminal and execute the following command:

$ sudo apt install stacer

Install Ghost CMS on Ubuntu 20.04 LTS - A step by step guide ?

This article covers the installation procedure of Ghost CMS on Ubuntu 20.04 LTS. In fact, Ghost is a lightweight, open-source Content Management System (CMS) and blogging platform built with Node.js. It is easy to install and update with Ghost-CLI.


How to Troubleshoot Ghost CMS ?

1. Troubleshoot the system for any potential issues when installing or updating Ghost:

$ ghost doctor

2. Get help about Ghost:

$ ghost --help

Install Gparted on CentOS 8 - A Step by Step guide ?

This article covers the best way to Install Gparted 'Gnome partition' editor on CentOS 8 system. In fact, Gparted (also known as GNOME partition editor) is a free partitioning tool that uses GNU parted in the backend. Gparted is used to create, delete, or resize a partition without data loss.


How to Create a new partition on CentOS 8 system ?

  • To create a new partition you need to have some free space on your disk.
  • Do this by right-clicking on it now click on New option this will open a new window fill the required information, and then click on Add.
  • Finally, click on the right tick (✔) given on the top to apply all the operations.

Install GPing on Linux Mint 20 - Best Method ?

This article covers the best method to get GPing installed on your Linux Mint 20 system. In fact, gping gives ping a nice graph in your Linux terminal.


How to Install gping on Linux Mint ?

On Linux Mint 20, /etc/apt/preferences.d/nosnap.pref needs to be removed before Snap can be installed. This can be accomplished from the command line:

$ sudo rm /etc/apt/preferences.d/nosnap.pref
$ sudo apt update

To install snap from the Software Manager application, search for snapd and click Install.

Alternatively, snapd can be installed from the command line:

$ sudo apt update
$ sudo apt install snapd

To install gping, simply use the following command:

$ sudo snap install gping

Configure Nginx Server Block and Secure Nginx with Let's Encrypt SSL on Rocky Linux 8 / CentOS 8

This article covers how you can configure an Nginx server block and secure your web server using Let's Encrypt SSL. In fact, Let’s Encrypt SSL certificate is a digital certificate provided by Let’s Encrypt CA ( Certificate Authority) to secure a web server.


How to Install Certbot on your RHEL-based distros / Linux system ?

1. First, install the EPEL repository which provides additional and high-quality packages for RHEL-based distros:

$ sudo dnf install -y epel-release

2. Once installed, install certbot and certbot module for Nginx:

$ sudo dnf install certbot python3-certbot-nginx

This installs certbot, certbot module for Nginx host of other packages and dependencies.

Install Vsftpd with SSL / TLS on Ubuntu 20.04 - Best Procedure ?

This article covers a complete guide on how to install Vsftpd with SSL/TLS on Ubuntu 20.04. In fact, sftpd (i.e. very secure FTP daemon) is an FTP server software for Linux and other Unix-like systems. An FTP server software facilitates the transfer of files from a client computer to the server and vice versa.

Encrypt Apache Webserver with Let's Encrypt SSL Certificate on Rocky Linux 8 - How to do it ?

This article covers how to secure your Apache webserver with Let's Encrypt SSL certificate. In fact, Let's Encrypt SSL certificates are yet another option for securing your web site with an SSL. Once installed, the system provides automatic renewal of certificates and will encrypt traffic to your web site.

Install Steam on CentOS 8 - Follow this guide ?

This article covers the installation procedure of the Steam application on CentOS using the Flatpak package management tool.

Install OwnCloud on Rocky Linux 8 - A step by step guide ?

This article covers how to successfully install OwnCloud on Rocky Linux 8. In fact, OwnCloud is an open source project that can be installed on your server to securely store and access files. Also allows you to share and collaborate contents that lets teams work on data easily from anywhere, on any device. With the support of a lot of plugins, Nextcloud becomes such a Collaboration software. You can install plugins for project management, video conferencing, collaborative editing, note-taking, email client, etc.


To Open port  80 in firewall, use the following command:

$ firewall-cmd --zone=public --add-port=80/tcp --permanent
$ firewall-cmd --reload


How to Install Apache or httpd web server on the Rocky Linux server ?

1. Simply Execute the dnf command below to install the httpd web server:

$ sudo dnf install httpd

Type "y" and press "Enter" to confirm and install httpd packages.

2. Now, enable and start the httpd service using the following command:

$ sudo systemctl enable httpd
$ sudo systemctl start httpd

The "systemctl enable" command will enable the service to start at every boot.

3. Finally, run the command below to verify the httpd service:

$ sudo systemctl status httpd

Install "exa" on Linux Mint 20 - Best Method ?

This article covers how to install "exa" on your system and use it as a replacement for the "ls" command in Linux Mint 20. In fact, exa is a modern replacement for the venerable file-listing command-line program ls that ships with Unix and Linux operating systems, giving it more features and better defaults. It uses colours to distinguish file types and metadata. It knows about symlinks, extended attributes, and Git. And it’s small, fast, and just one single binary. Using this modern tool will simply allow you to visualize your files and directories in Linux in a much better way.

Install bpytop on Linux Mint 20 - Complete guide ?

This article covers how to install bpytop tool on a Linux Mint 20 system. In fact, BpyTop is a Linux command-line utility for resource monitoring. It shows usage and stats for processors, memory, disks, network, and processes. With this tool installed on your system, you can use it very efficiently for resource usage monitoring.

To check the version of Python running on your Linux distribution, type:

$ python3 --version

After installing Bpytop, you can start monitoring your Linux system resources by running the command below:

$ bpytop

Install GlassFish on CentOS 8 - A step by Step guide ?

This article covers how to install the GlassFish application server on CentOS 8. In fact, GlassFish allows developers to create enterprise applications that are portable and scalable, and that integrate with legacy technologies. Also, you will see the best way to define systemd services for running Glassfish server and firewall configurations. 

To Start and enable glassfish services, simply run the below command:

$ systemctl start glassfish.service
$ systemctl enable glassfish.service
To access Glassfish Server on CentOS / RHEL 8, simply browse the below URL to access Glassfish Admin Console, ignore the certificate warning or install it:
https://SERVER-IP-OR-DOMAIN-NAME:4848/

Install Juju on Linux Mint 20 - Step by step procedure ?

This article covers how you can install Juju on any Linux distribution. In fact, the Juju client is a single binary executable that is published and supported on multiple operating systems and CPU architectures. 

To Install Juju on Linux from snap, run the below command:

$ sudo snap install juju --classic


To Install Juju on macOS, run the below command:

$ brew install juju

Install Ruby on CentOS 8 - A step by step guide ?

This article covers steps to Install Ruby and run ruby applications on your centos 8 machine. In fact, Ruby is a dynamic, object-oriented programming language focused on simplicity and productivity. RVM (Ruby Version Manager) is a tool for installing and managing multiple Ruby versions on single operating systems. 


To Verify Active Ruby Version installed on your Linux system, run the below command:

$ ruby --version

Install ImageMagick on CentOS 8 - Step by Step process ?

This article covers how to install ImageMagick on the CentOS machine via different methods. Infact, ImageMagick provides a graphical interface for working with images, it also provides commands to resize an image, blur, crop, draw on, flip, join, re-sample, and much more.

Install and Configure Redis on CentOS 8 - Step by Step Procedure ?

This article covers the complete Installation guide of Redis on the CentOS 8 system. Redis is an open-source in-memory data structure store. In fact, You can use it as a Memcached alternative to store simple key-value pairs, as a NoSQL database, or even a message broker with the Pub-Sub pattern.

Also, Redis supports data structures such as strings, hashes, lists, sets, sorted sets with range queries, bitmaps, HyperLogLogs and geospatial indexes with radius queries. Redis has built-in replication, Lua scripting, LRU eviction, transactions and different levels of on-disk persistence, and provides high availability via Redis Sentinel and automatic partitioning with Redis Cluster.

Install MariaDB on Rocky Linux 8 - Step by Step Process ?

This article covers step-by-step installation procedure of the MariaDB server on Rocky Linux 8. In fact, MariaDB was developed as a "drop-in" replacement for MySQL. As such, both software packages are functionally equivalent and interchangeable.

To enable MariaDB service to start on boot time and start the service using the following commands:

$ sudo systemctl enable mariadb
$ sudo systemctl start mariadb

To verify the running status of MariaDB, run the below command:

$ sudo systemctl status mariadb

Install Cacti on Ubuntu 20.04 LTS - Step by Step Process ?

This article covers step by step procedure for installing the Cacti monitoring tool on Ubuntu 20.04 LTS. In fact, Cacti is a free and open-source RRD tool-based network monitoring tool that monitors network devices such as servers, routers, and switches. Cacti uses the SNMP protocol to gather data from remote systems. Data gathered is then stored in a MySQL database. 

One of the most essential tasks that any IT operation team has to keep in mind is continuous monitoring of their IT infrastructure. The concept of monitoring ensures that systems such as servers are functioning and working as desired.

Install LAMP Stack on CentOS 8 - Step by Step Process ?

This article covers how to install the LAMP stack on the CentOS system. If are using another Linux distribution, visit how to install LAMP stack on Debian, Ubuntu, Red Hat, and Rocky Linux. Basically, A LAMP stack is a collection of open-source software that you can use as a platform to create websites and web applications. The term LAMP is an acronym standing for Linux operating system, the Apache HTTP Server, the MySQL database system, and the PHP programming language.


In LAMP:

  • Linux serves as the server's operating system that handles all the commands on the machine.
  • Apache is a web server software that manages HTTP requests to deliver your website's content.
  • MySQL is a relational database management system (RDBMS) whose function is to maintain user's data on a server.
  • PHP is a scripting language for server-side communication.

Install Webmin on Rocky Linux 8 - Step by Step Process ?

This article covers steps to Install and configure Webmin on Rocky Linux 8 using the automated installation script. Webmin web interface is used to set up user and disk management, Apache, DNS, PHP, MySQL, check CPU usage, system info, network config, and more.


How to Install Webmin using RPM package ?

It is also possible to install Webmin using the rpm package available on the download page of Webmin. This is the quickest way to get Webmin up and running on your Linux machine.

1. Install dependencies

Since Webmin is written in Perl, you need to install Perl and its dependencies:

$ sudo dnf install perl perl-Net-SSLeay perl-Data-Dumper perl-Encode-Detect

2. Download and Install Webmin RPM package

This will install the latest version of Webmin using the rpm package:

$ sudo dnf install https://www.webmin.com/download/rpm/webmin-current.rpm


How to uninstall Webmin ?

You can simply uninstall Webmin using the script /etc/webmin/uninstall.sh.

Install PHP 8.0 on Rocky Linux 8 - Best Procedure ?

This article covers steps to install PHP 8.0 in Rocky Linux. PHP is used to develop static or dynamic websites or web applications. Many popular CMS such as WordPress, Magento, and Joomla is written in PHP. Frameworks such as Laravel, Symfony, and CodeIgniter is also using PHP.

To list the available PHP version on your Linux terminal, run the command:

$ sudo dnf module list php

To verify PHP version, simply run the command:

$ php -v 

To install PHP packages and dependencies, run the command:

$ sudo apt install php php-cli php-fpm php-json php-common php-mysql php-zip php-gd php-mbstring php-curl php-xml php-pear php-bcmath


How to Install PHP 7.4 on Ubuntu ?

Installing PHP 7.4 on Ubuntu 19.04/18.04 is a bit different than 20.04. 1. To get started, update apt and add the required repositories:

$ sudo apt-get update
$ sudo apt -y install software-properties-common
$ sudo add-apt-repository ppa:ondrej/php
$ sudo apt-get update

2. And begin the install.

$ sudo apt install php7.4

3. After the install is complete, you can check the version that is installed and in use.

$ php -v

Check Internet speed from command line in Linux Mint

This article covers different ways to measure and monitor your internet bandwidth in Linux Mint System. Speedtest CLI is a command-line tool that is tailored for system administrators and developers, and command-line enthusiasts. It provides the capability of checking the internet speeds straight from your Linux terminal.


Speedtest CLI allows you to do the following:

  • Check the bandwidth performance including metrics such as download, upload, and packet loss.
  • Check the connection from your PC or even a remote server and IoT devices such as Raspberry Pi.
  • Configure scripts to collect speed test results over a period of time.
  • Save results in CSV or JSON.


How to Check version of Speedtest-cli in Linux Mint ?

To check the version of the Speedtest-cli tool, run the command:

$ speedtest-cli --version

Install PgAdmin 4 on Rocky Linux 8 - Step by Step Process ?

This article covers how you can Install and easily get started with PgAdmin4 for your Linux system. pgAdmin is an advanced, open-source, full-featured, and web-based administration and management tool for the PostgreSQL database server.

Install TensorFlow on CentOS 8 - Step by Step Process ?

This article covers the installation procedure of TensorFlow on CentOS 8 system. TensorFlow is a machine learning platform by Google. It is basically an open source and has a huge number of tools, libraries and other resources developed by both its developer community as well as Google and other corporations.

TensorFlow is available for all the popularly used operating systems, viz. Windows, Mac OS, GNU/Linux. It can be downloaded and installed from either Python Package Index using the pip tool and can be run in a virtual python environment. Another way to use it is to install it as a Docker container.

Rkhunter for Scanning Backdoors, Rootkits, and Local Exploits in Your Ubuntu Linux System - How to use it ?

This article covers an easy procedure to install rkhunter, configure, scan the system and view log to identify actual backdoor, rootkits, and local exploits. In fact, Rkhunter (Rootkit Hunter) is an open-source Unix/Linux based scanner tool for Linux systems released under GPL that scans backdoors, rootkits, and local exploits on your systems. It scans hidden files, wrong permissions set on binaries, suspicious strings in the kernel, and so on. 

To scan the entire Linux  file system, run the Rkhunter command as a root user:

$ rkhunter --check

Install and Use Logwatch on Ubuntu 20.04 - Step by Step Guide ?

This article covers how to install and use Logwatch on Ubuntu Linux System. Logwatch is a system log analyzer and send that report to email. It generates a summarized log report which contains sshd - authentication failures, sudo - sessions opened, vsftp failures, postfix, failed logins, disk space and more. To find more information, visit the Logwatch man page.

Logwatch can be installed simply from the Ubuntu repository. First update the system.

$ sudo apt-get update

To install Logwatch, execute the command:

$ apt-get install logwatch

Install Zoom Client on AlmaLinux / Rocky Linux 8 - Step by Step guide ?

This article covers Zoom client's installation procedure. You can now proceed and start or join meetings with the security and reliability that Zoom provides.

Install Kong API Gateway on Ubuntu 20.04 - Step by Step Process ?

This article covers how to install the KONG API Gateway on Ubuntu 20.04. These Gateways provides services like Authentication, rate-limiting, analysis, logging etc., to your API endpoints.

To Start kong API, run the following commands:

$ kong migrations up #runs the database migrations
$ sudo kong start
$ curl -i http://localhost:8001

To Stop and see status of kong API, run the following commands:

$ sudo kong stop #stop kong
$ sudo kong health #kong status

Install NtopNG on Linux Mint 20 - Step by Step Process ?

This article covers easy steps to install the NtopNG utility on your Linux Mint 20 system. Once it is installed on your system, you can start using it for network traffic monitoring after configuring it according to the specifications of your machine.

To check whether NtopNG is installed or not, run the command:

$ systemctl status ntopng

To start NtopNG service, execute the command:

$ systemctl start ntopng

Start, Stop or Restart Services in CentOS 8 - Step by Step Process ?

This article covers how to start, stop and restart the httpd service on CentOS 8 system with the help of the systemctl command. Using this utility, you can easily control any systemd and server-wide service on your system. 

Linux provides fine-grained control over system services through systemd, using the systemctl command. Services can be turned on, turned off, restarted, reloaded, or even enabled or disabled at boot. If you are running Debian 7, CentOS 7, or Ubuntu 15.04 (or later), your system likely uses systemd.

Install Siege on Linux Mint 20 - Step by Step Process ?

This article covers how to quickly install the Siege tool on your Linux system and use it to test any specific web server. Siege is an open-source multi-threaded regression test and benchmark utility with a primary focus on load testing and benchmarking. It can stress test a single URL with a user-defined number of simulated users or read many URLs into memory and stress them simultaneously. The program reports the total number of hits recorded, bytes transferred, response time, concurrency, and return status.


To Install Siege Benchmarking Tool on Ubuntu / Debian,

1. Check and update your Ubuntu 20.04 operating system:

$ sudo apt update && sudo apt upgrade -y

2. Install Siege execute the following command:

$ sudo apt install siege -y

3. Confirm the siege version to make sure it's installed and to compare it to the current version from Siege's official website:

$ siege --version

Install Node.JS on Rocky Linux 8 - Step by Step Process ?

This article covers the Installation process of NodeJS on Rocky Linux. Nodejs is a JavaScript runtime built on Chrome's V8 JavaScript engine and is designed to build scalable network applications.

Install and Use Logwatch on Linux Mint 20 - Step by Step Process ?

This article covers how to install the Logwatch utility on your Linux server. With Logwatch, you will be able to keep an eye on your server logs and hence, you can quickly figure out any possible issues.

You can easily customize Logwatch to your preference by modifying the parameters in the /etc/logwatch/conf path. It also provides something extra in the way of pre-written PERL scripts for making log parsing easier.

All the default settings are defined in the /usr/share/logwatch/default.conf/logwatch.conf file. The recommended practice is to leave this file intact and instead create your own configuration file at the /etc/logwatch/conf/ path by copying the original config file and then define your custom settings.


Logwatch comes with a tiered approach and there are 3 main locations where configuration details are defined:

  • /usr/share/logwatch/default.conf/*
  • /etc/logwatch/conf/dist.conf/*
  • /etc/logwatch/conf/*


To install Logwatch on your server.

On Ubuntu:

$ sudo apt-get install logwatch

On Debian:

$ apt-get install logwatch

Install Dropbox on Centos 8 - Step by Step Process ?

This article covers how you can install Dropbox on the CentOS system and sync your local files and folders with Dropbox cloud storage. Dropbox is a useful file-sharing and syncing service that lets you sync files between different machines over the Internet for free. It's very useful for backing up your important documents, pictures, MP3 files, video files, and other data.

Install Grafana on Ubuntu 20.04 - Step by Step Process ?

This article covers how to install Grafana on Ubuntu OS using two methods: using the APT repository and the .deb package. Grafana is multi-platform open-source analytics and interactive visualization web application that integrates with complex data from sources like Prometheus, InfluxDB, Graphite, and ElasticSearch. It provides charts, graphs, and alerts for the web when connected to supported data sources. It is expandable through a plug-in system.


Features of Grafana:

  • Data Visualization: Allows for fast and flexible visualization with many options and settings.
  • Dynamic Dashboards: Provides the ability to create dynamic and reusable panels with templated variables.
  • Metrics Exploration: Explore your data with ad-hoc queries and dynamic drill-down by splitting the view and comparing different time ranges and sources.
  • Data Logs: Provides tremendous opportunities to use data metrics in a log with labels and filters saved, which can be studied, viewed, and broadcasted.
  • Extensive Alert Capabilities: Visually define alert rules for your most important metrics. Grafana will continuously evaluate and send notifications to systems such as Slack, PagerDuty, VictorOps, and OpsGenie.
  • Mixed Data Sources: Mix different data sources on the same graph and for each query.

Migrate to AlmaLinux 8.4 from CentOS Linux - Step by Step Process ?

This article covers the process of migrating to AlmaLinux from CentOS 8. AlmaLinux OS is a new RHEL fork from the team at CloudLinux. It is meant to be a free Linux Operating System, developed in close co-operation with the community, and for the community. As of this article update, the release of AlmaLinux available is not stable fit for production use. AlmaLinux OS is now stable and can be used in Production environments.


To Migrate from CentOS 8 To AlmaLinux 8.4.

1. Download the almalinux-deploy.sh script:

$ curl -O https://raw.githubusercontent.com/AlmaLinux/almalinux-deploy/master/almalinux-deploy.sh

2. Give the script execution bits:

$ chmod +x almalinux-deploy.sh

3. Then run the script with the commands below:

$ sudo bash ./almalinux-deploy.sh

Add a User to Sudoers on Debian 10 - Step by Step Process ?

This article covers how to add users into the sudoers group. Also you will learn how to edit rules in the sudoers configuration file through the command. You can customize the sudoers file based on the user requirements. Sudo stands for superuser do. Sudo is a command used in Unix-like systems to allow a regular user to execute a program as another user. In most cases, it is the root user.

The sudo command allows authorized users to perform commands as another user, which is by default the root user. 

This option gives you administrator-level permissions to run programs on your machine. It is an alternative to using the su command.

Install Cockpit on CentOS 8 - Step by Step Process ?

This article covers how you can easily install Cockpit on your CentOS system and manage other Linux servers. With Cockpit, you can have a quick glance at the performance of all your added servers. Also, you can monitor system resources, start and stop services, shut down the system, install updates, view network activity (send/received). create or remove user accounts, access Terminal, and much more on the remote servers. Cockpit helps to save a lot of time by letting the administrators manage the remote servers that are spread across the network using a lightweight and intuitive interface. 


Benefits of Cockpit in our GNU/Linux servers:

  • It consists of systemd service manager for ease.
  • It has a Journal log viewer to perform troubleshoots and log analysis.
  • Storage setup including LVM was never easier before.
  • Basic Network configuration can be applied with Cockpit
  • We can easily add and remove local users and manage multiple servers.


To Install  and enable Cockpit packages from repository, run the command:

$ sudo yum install cockpit

Type "y" and it will start downloading and installing the required packages.

To enable the Cockpit with the following command:

# sudo systemctl start cockpit

or

$ sudo systemctl enable --now cockpit.socket


To confirm the status of Cockpit, run the command:

# sudo systemctl status cockpit

Migrate from CentOS 8 To Rocky Linux 8 - Step by Step Process ?

This article covers how to easily migrate to Rocky Linux 8.4 from CentOS 8. Rocky Linux is a community enterprise operating system designed to be 100% compatible with RedHat Enterprise Linux. Rocky Linux dev team has created a migration script called migrate2rocky to easily convert an existing CentOS 8 system to Rocky Linux 8.


To Upgrade the current CentOS 8 Linux system to latest available version, run the command:

$ sudo dnf --refresh upgrade

After update is completed, Reboot your system:

$ sudo reboot

Install GIMP on CentOS 8 - Best Method ?

This article covers how you can easily install the GIMP image editor on your CentOS system. GIMP is the acronym for GNU Image Manipulation Program. It is free and open source raster graphics editor used for image retouching and editing, free form drawing, converting between image formats and many more tasks. It is released under GPL3 license and is available for Linux, Microsoft Windows and MacOS.


How to Install and use Gimp graphical editor on Linux?

You can install gimp package by using the dnf command:

# dnf install gimp

You can Start Gimp graphical editor from your menu or by executing the following command:

$ gimp

Install OpenLiteSpeed Webserver on Ubuntu 20.04 - Easy method ?

This article covers how to install and configure OpenLiteSpeed webserver. OpenLiteSpeed is an easy-to-use, open-source web server. It offers unbeatable features and performance to your sites along with top-notch security. Also, it understands all the apache rewrite rules and has intelligent cache acceleration features that let you implement the fastest caching on your server. Apart from all these, you get to install a customized PHP processor that is optimized for the OpenLiteSpeed server.


OpenLiteSpeed server's Frontend (default page) is located at:

http://<your-server-public-IP>:8088

It's backend (admin console) is located at:

https://<your-server-public-IP>:7080

Install Apache Maven on CentOS 8 - Easy Method ?

This article covers the installation methods( Yum package manager or via direct download method), you can easily install Apache Maven on CentOS. Apache Maven is basically a software project management and comprehension tool. 


How to check Apache Maven on Linux?

Use the following command to check the version of installed Maven on your system:

$ mvn -version

Disable SELinux on CentOS 7 - How to do it ?

This article covers method to permanently disable SELinux on CentOS 7. SELinux, also known as Security-Enhanced Linux, is a security feature embedded in the Linux kernel. SELinux leverages Mandatory Access controls (MAC) to confine users to certain rules and policies and prevents them from performing unauthorized tasks on the Linux system as specified by the IT administrator

To Check SELinux status, simply run the command:

# sestatus

Install PostgreSQL 13 on Rocky Linux - Best Method ?

This article covers PostgreSQL 13 installation on Rocky Linux 8.4. Basically, PostgreSQL is the world's most advanced open source database system. And with the release of PostgreSQL 13 there are significant improvements to the indexing and lookup system that benefit large databases, and faster response times for queries that use aggregates or partitions.


How to Enable and Start PostgreSQL Service ?

To enable and start the PostgreSQL database service so that it can start automatically with system boot:

$ sudo systemctl start postgresql-13
$ sudo systemctl enable postgresql-13

To confirm everything is working fine, check the status of PostgreSQL service:

$ sudo systemctl status postgresql-13

Install Gitea on Ubuntu 20.04 - Best Method ?

This article covers how to install Gitea on Ubuntu 20.04 LTS. Gitea is a self-facilitated open-source git worker written in Go. It is a fork of Gogs . Gitea incorporates a store record supervisor, venture issue following, clients administrations, notices, implicit wiki, and considerably more. 

To Install Git on Linux, run the commands: 

$ sudo apt update
$ sudo apt install git

To Confirm Git Installation, execute the command: 

$ git --version

Install Puppet on Ubuntu 20.04 - Best Method ?

This article covers the installation of a puppet server on both master and client nodes and how to connect them. Ensure that you sign the puppet agent node certificate for both the master and client-side.

Puppet is a free and open-source automated administrative engine for Linux, Unix, and Windows operating systems. It is used for deploying, configuring, and managing servers and performs administrative tasks such as adding users, installing packages, and many more. It helps system admins to free up time and mental space by automating tasks on thousands of physical and virtual machines. It uses a client-server model. Where Puppet master controls configuration information for Puppet agents while Puppet agents talk to and pull down configuration profiles from the Puppet master.

Install Flatpak on CentOS 8 - Best Method ?

This article covers the installation steps of Flatpak on the CentOS 8 system. With Flatpak, users can easily install new packages or applications from the flathub repository in an isolated space.

Flatpak is a package management system that aims to enable  users and developers to install and manage software packages on Linux systems regardless of the Linux distribution, runtime, dependencies and the type of package management. A flatpak application runs in a sandboxed environment. This is an isolated environment that is bundled with all the dependencies, libraries and everything that is needed for the app to run smoothly. 


How to Enable Flatpak in Red Hat / CentOS / Fedora ?

For RedHat / CentOS 8 and Fedora 22 and later versions, invoke the command below to enable flatpak:

$ sudo dnf install flatpak

For earlier versions of Red Hat and CentOS use the YUM package manager:

$ sudo yum install flatpak

Install and Configure Monit Monitoring Server on Ubuntu 20.04 LTS - Best Method ?

This article covers how to Install Monit monitoring server on the Ubuntu 20.04 system. Monit is an open-source utility used to supervise the processes and restart the services which are configured for it and have failed. Monit supervises the processes and restarts them on failure detection. Apart from the processes, Monit can also be used to monitor CPU, RAM, Disk, File Size and trigger alerts on out-of-bound values. It also shows how to trigger alert emails using custom templates. 

Now you can easily monitor your system using this lightweight tool.


To Install Monit on Ubuntu, run the following commands:

$ sudo apt update
$ sudo apt install monit

Add Users to Sudo Group On Linux Mint 20 - Best Method ?

This article covers how to add and remove users in the sudo group to manage the sudo privileges of the users. sudo is a command-line program that allows trusted users to execute commands as root or another user.

Enable SSH on CentOS 8 - Best Method ?

This article covers how to enable SSH on a CentOS machine and connect to it using a client machine. If you want to make your remote access secure, Read our post on the Best Ways to Secure Your SSH Server.

SSH provides the ability to transfer files between remote systems. When a user logs into a remote system using SSH, they receive a command prompt allowing them to enter commands on the remote system as if they were sitting at the remote system and had opened a terminal session.


How to Install OpenSSH Server Software Package ?

Enter the following command from your terminal to start the installation process:

$ sudo yum –y install openssh-server openssh-clients

This command installs both the OpenSSH client applications, as well as the OpenSSH server daemon, sshd.

Install Emacs Editor on CentOS 8 - Best Method ?

This article covers different methods to install the emacs editor on CentOS 8 system. Emacs is one of the oldest and most versatile text editors available for Linux and UNIX-based systems. It's been around for a long time (more than twenty years for GNU emacs) and is well known for its powerful and rich editing features. Emacs is also more than just a text editor; it can be customized and extended with different "modes", enabling it to be used like an Integrated Development Environment (IDE) for programming languages like Java, C or Python.


To Install Emacs via EPEL repository, Run the following command:

$ sudo dnf update
$ sudo dnf install epel-release
$ sudo dnf install emacs

Install Elasticsearch on CentOS 8 - Best Method ?

This article covers the installation and basic configuration of Elasticsearch on the CentOS system. For how to use Elasticsearch, visit the Quick start guide available on its website. Elasticsearch is an open source search and analytics engine that allows you to store, search, and analyze big volumes of data in real time. Elasticsearch powers millions of Applications that rely on intensive search operations such as e-commerce platforms and big data applications. 

Elasticsearch supports RESTful operations. This means that you can use HTTP methods (GET, POST, PUT, DELETE, etc.) in combination with an HTTP URI (/collection/entry) to manipulate your data. The intuitive RESTful approach is both developer and user friendly, which is one of the reasons for Elasticsearch's popularity.

Install KDevelop in Ubuntu 20.04 - Best Method ?

This article covers How to Install kdevelop in Ubuntu Linux System. KDevelop is a robust IDE that includes useful extensions, and also several high-quality features. KDevelop is a great option of IDE for Linux distributions due because of its stability and security.

To Install kdevelop software package in Ubuntu, run the following command:

$ sudo apt-get update
$ sudo apt-get install kdevelop

Add and Remove User in CentOS 8 - Best Method ?

This article covers how to add a user as well as how to remove it in case you no longer need it. We also described how to add and remove a user to and from a group. If you are using Ubuntu distribution, visit how to add or remove users in Ubuntu

You may need to create separate account for every user want to connect this system. To add new users in system there are two commands available in your system, useradd and adduser. adduser command is the enhanced version of useradd command. adduser command uses useradd command in backend. 

Install and Run Jenkins with Systemd and Docker on Ubuntu 20.04 - Best Method ?

This article covers how to Run Jenkins Server in Docker Container with Systemd. Jenkins is an opensource automation server that is designed to help software developers build, test and deploy applications and thereby streamline the continuous integration and delivery process. 

To create a system group for Jenkins, run the command:

$ sudo groupadd --system jenkins

Then create Jenkins system user:

$ sudo useradd -s /sbin/nologin --system -g jenkins jenkins

And finally add Jenkins user to docker group as shown:

$ sudo usermod -aG docker jenkins

To confirm that Jenkins user is added to the docker group, run the id command as shown:

$ id jenkins

Change SSH Port on Ubuntu 20.04 Linux System - Best Method ?

This article covers how to change the ssh port on Ubuntu Linux server. You can easily change the SSH Port for Your Linux server. For better security, consider using SSH passwordless authentication with SSH public/private key pair.

The ssh port defined in sshd_config file. This file located in /etc/ssh/sshd_config location.

To open the new port run the following commands on Fedora/CentOS/RHEL/Oracle Linux using FirewallD:

$ sudo firewall-cmd --permanent --zone=public --add-port=2222/tcp
$ sudo firewall-cmd --reload


How to Restart the sshd service ?

Type the following command on a CentOS/RHEL/Fedora Linux:

$ sudo service sshd restart

OR if you are using CentOS/RHEL/Fedora Linux with systemd:

$ sudo systemctl restart sshd

OR if you are using Ubuntu/Debian/Mint Linux:

$ sudo service ssh restart

OR if you are using Ubuntu/Debian/Mint Linux with systemd:

$ sudo systemctl restart ssh

Or if you are using FreeBSD Unix, enter:

$ sudo service sshd restart

Install Harbor Image Registry on Ubuntu 20.04 - Best Method ?

This article covers how to install harbor on Ubuntu. The process is the same for all the other distribution of Linux. Harbor is a component of vSphere with Kubernetes. Harbor provides an enterprise-class registry service. 

Harbor is deployed in a dedicated system namespace on the Supervisor Cluster and is composed of several vSphere Pods. 

Image registries provide a centralized repository for an organization to store container images. 

Public image registries can be used to store container images. However, for security reasons, it is better to use an on-premises image registry. 

You use an on-premises image registry for the following purposes: 

Store container images securely. 

Control access to container images. 

vSphere with Kubernetes is integrated with Harbor and is also compatible with other container image registries. 


Harbor key features includes:

  • Security and vulnerability analysis.
  • Content signing and validation.
  • Extensible API and web UI.
  • Image replication.
  • Role-based access control.
  • Multitenant.


After Harbor installation has succeeded, access Harbor web console on https://registry_domain.

Then Login with:

  • Username: admin
  • Password: Set-in-harbor.yml

Install Emacs Editor in Debian 10 - Best Method ?

This article covers the different methods to install Emacs on Debian OS. Emacs is a widely used open-source text editor for Linux. It exists for many years now and can be used for basic word processing, code editing, and scripting, etc.


How to Install Emacs editor on Debian ?

1. To start the installation process, login with root and update the package repository with the following command.

$ apt-get update

2. Next, run the following command on the terminal and wait for the operation to complete. This can take several minutes. When you are asked for confirmation, press Y from your keyboard.

$ apt-get install emacs

Install Notepadqq on Ubuntu 20.04 - Best Method ?

This article covers how to install notepadqq on Ubuntu 20.04 Linux system. Notepad is a similar copy of the most popular editor notepad++. Basically, Notepadqq is a text editor that is designed by developers for the developers. It supports more than 100 languages and useful to note down daily tasks.


How to Install Notepadqq on Debian / Ubuntu?

1. Add Repository

$ sudo add-apt-repository ppa:notepadqq-team/notepadqq  

2. Update Repository

$ sudo apt-get update  

3. Install Notepadqq

$ sudo apt-get install notepadqq  

4. After installation, we can access it either via terminal by typing notepadqq or by searching from the application manager. Run Notepadqq:

$ notepadqq 

Install Putty on CentOS 8 - Best Method ?

This article covers how to Install putty on CentOS 8. With putty, you can easily connect your Linux system to a remote system. Putty is a free and open source ssh & telnet client. Putty is available for Windows, Linux, Unix and macOS. Using putty, we can access the remote servers and switches over ssh protocol. It can also be used to take serial console of remote systems.


How to perform Putty Installation on CentOS / RHEL / Fedora ?

Putty package is available in the default CentOS and RHEL repositories. So, to install putty run:

$ sudo yum install putty -y

Or

$ sudo dnfs install putty -y

Install Nmap on CentOS 8 - Best Method ?

This article covers methods to install Nmap on your CentOS machine. Nmap is a handy utility for network scanning and security auditing. Nmap contains variety of options for scanning remote hosts. Have a look at the 15 Mostly Used Nmap Commands for Scanning Remote Hosts.



How to Install Nmap on Debian / Ubuntu ?

1. Install Nmap on Ubuntu by entering the following command:

$ sudo apt-get install nmap

2. The system prompts you to confirm the installation by typing y.

3. After the installation is finished, verify the installed version of Nmap by entering:

$ nmap –version

Install Go on CentOS 8 - Best Method ?

This article covers how to install Go on CentOS 8. Go language was designed to resolve the common criticisms of other languages while maintaining their positive characteristics and most widely used for writing servers these days.


Run the below command to see the version of the Go language:

$ go version

Install NetBeans on CentOS 8 - Best Method ?

This article covers the installation of Apache NetBeans on the CentOS system. Here, you will learn the entire procedure for the installation of NetBeans that includes downloading, installation, and launching of NetBeans. At the end, you also learned to uninstall Apache NetBeans if you ever have to do that.

Apache NetBeans is a very powerful Integrated Development Environment (IDE) tool that enables you as a Developer create Desktop, Web and Mobile Applications from its modular framework. It supports Java, PHP, HTML, JavaScript, C, C++, Ajax, JSP, Ruby on Rails and other programming languages using extensions.

Install and Use Vim Editor in Linux - Best Method ?

This article covers how to install vim, followed by some basics on using vim and then uninstalling it. Vim (Vi IMproved) is a text editor that is upwards compatible to Vi. It can be used to edit all kinds of plain text. It is especially useful for editing config files and programs written in shell, python, perl, c/c++ and more. 

Among the various text editors in the world of Linux, Vim (or Vi IMproved) stands out for its versatility and for the functions it offers. In fact, Vim is able to speed up code writing, providing some shortcuts to perform all the operations of modification, deletion or replacement of the text. 

Vim Text Editor also allows you to install different plugins through which transforming this simple text editor into a real IDE for programming in different languages.


How to Install vim using apt on Linux ?

1. Open terminal application. You can also press CTRL+ALT+T keyboard shortcut.

2. Update package database by typing the sudo apt update command.

3. Search for vim packages run: sudo apt search vim.

4. Install vim on Ubuntu Linux, type: sudo apt install vim.

5. Verify vim installation by typing the vim --version command.

Install Nginx on CentOS 8 - Best Method ?

This article covers how to install the Nginx server on a CentOS machine and add a firewall rule to allow traffic coming towards the Nginx server. Also, we've discussed how to remove Nginx from CentOS.

The Nginx is a free, open source, lightweight and high-performance web server designed for high-traffic use cases. It is also acting as a popular Web server behind the Apache Web server and Microsoft's IIS. Nginx is more resource-friendly than Apache. It can be served in front of other web servers as a reverse proxy.


How to Install Nginx Web Server ?

1. Install the nginx package with:

$ sudo dnf install nginx

2. After the installation is finished, run the following commands to enable and start the server:

$ sudo systemctl enable nginx
$ sudo systemctl start nginx

This will make Nginx start at system boot.

Install Java on CentOS 7 System - Best Method ?

This article covers how to install and manage multiple Java versions on CentOS 7 system. At the end you also learned how to set default Java version. Java is used for developing anything from lightweight mobile to desktop applications.


How to Install Java 8 on CentOS ?

1. Update the system before installing any new programs:

$ yum -y update

2. Install Java 8:

$ yum install java-1.8.0-openjdk

3. Verify Java is Installed

$ java -version

Check CentOS Version - Using Different methods ?

This article covers how to get CentOS version using different methods. There are several ways on how to check what version of CentOS is running on your system. The simplest way to check for the CentOS version number is to execute the cat /etc/centos-release command. Identifying the accurate CentOS version may be required to help you or your support team to troubleshoot your CentOS system.


Different commands to check CentOS version:

  • $ rpm -q centos-release - CentOS version valid for CentOS 6 and higher. Causes to reveal major, minor and asynchronous CentOS version.
  • $ lsb_release -d - Requires redhat-lsb package to be installed before execution.
  • $ rpm -E %{rhel} - RPM macro to reveal a major CentOS version.
  • $ rpm --eval %{centos_ver} - RPM macro to display a major version of CentOS.
  • $ cat /etc/centos-release - Linux cat command to output content of the /etc/centos-release .to query CentOS version. Works with CentOS 6 and higher.

Install and Use Curl command on CentOS 8 - Step by Step Process ?

This article covers how to install the Curl command-line tool on CentOS 8 system. Through the curl command, users can download and upload files over the network. curl is a powerful command-line tool for transferring data from or to a remote server. With curl you can download or upload data using various network protocols, such as HTTP, HTTPS, SCP , SFTP , and FTP .


How to Install curl on CentOS ?

Curl package is available in the standard CentOS 8 repositories. 

To install it run the following command:

$ sudo dnf install curl

Once the installation is complete, verify it by typing curl in your terminal:

$ curl

Install LAMP Stack on CentOS 7 - Step by Step Process ?

This article covers how to install LAMP stack on CentOS 7. LAMP is a stack of applications that work together on a web server to host a website. With that being said, each individual program serves a different purpose.

In LAMP: 

  • Linux serves as the server's operating system that handles all the commands on the machine.
  • Apache is a web server software that manages HTTP requests to deliver your website's content.
  • MySQL is a relational database management system (RDBMS) whose function is to maintain user's data on a server.
  • PHP is a scripting language for server-side communication.


To install Apache easily using CentOS's package manager, yum:

1. Run the command.

$ sudo yum install httpd

2. Once it installs, you can start Apache on your server.

$ sudo systemctl start httpd.service

3. You can do a spot check right away to verify that everything went as planned by visiting your server's public IP address in your web browser.

http://your_server_IP_address/


Important PHP Modules:

  • php-bcmath.x86_64 : A module for PHP applications for using the bcmath library.
  • php-cli.x86_64 : Command-line interface for PHP.
  • php-common.x86_64 : Common files for PHP.
  • php-dba.x86_64 : A database abstraction layer module for PHP applications.
  • php-devel.x86_64 : Files needed for building PHP extensions.
  • php-embedded.x86_64 : PHP library for embedding in applications.
  • php-enchant.x86_64 : Enchant spelling extension for PHP applications.
  • php-fpm.x86_64 : PHP FastCGI Process Manager.
  • php-gd.x86_64 : A module for PHP applications for using the gd graphics library.

Install Skype on CentOS 7 System - Step by Step Process ?

This article covers how to install Skype on your CentOS 7 desktop system. Running Skype on CentOS/Fedora allows you to make Skype calls, group video calls, instant messaging, phone number calls, and screen sharing.


How to Install Skype on CentOS | Fedora ?

The easiest and quickest way to install Skype on Fedora 34/33/32/31/30 is by using the RPM package. 


1. Download the package using wget command:

$ wget https://repo.skype.com/latest/skypeforlinux-64.rpm

2. Install Skype by running the commands:

### On CentOS and Red Hat systems ###
$ sudo yum localinstall skypeforlinux-64.rpm
### On Fedora 22+ systems ###
$ sudo dnf localinstall skypeforlinux-64.rpm

3. Use the following command to launch Skype from the command line and accept terms and conditions for the first time.

$ skypeforlinux

Set Up SSH Keys on CentOS 7 - Step by Step Process ?

This article covers how to create a new SSH key pair and set up an SSH key-based authentication. You can set up same key to multiple remote hosts on CentOS system. Also, you will learn how to disable SSH password authentication.

SSH, or secure shell, is an encrypted protocol used to administer and communicate with servers. When working with a CentOS server, chances are, you will spend most of your time in a terminal session connected to your server through SSH.

SSH keys are typically configured in an authorized_keys file in . ssh subdirectory in the user's home directory. Typically a system administrator would first create a key using ssh-keygen and then install it as an authorized key on a server using the ssh-copy-id tool.

The public key should be stored in the ~/. ssh/authorized_keys file on the server.


To Create the RSA Key Pair:

1. Execute the command below to create a key pair on the client machine (usually your computer):

$ ssh-keygen

2. Press ENTER to save the key pair into the .ssh/ subdirectory in your home directory, or specify an alternate path.


Best Practices to improve SSH Key Security:

  • Discover all SSH Keys and Bring Under Active Management.
  • Ensure SSH Keys Are Associated With a Single Individual.
  • Enforce Minimal Levels of User Rights Through PoLP.
  • Stay Attentive to SSH Key Rotation.
  • Eliminate Hardcoded SSH Keys.
  • Audit All Privileged Session Activity.

Stop and Disable Firewalld on CentOS 7 - Step by Step Process ?

This article covers how to stop and disable FirewallD on your CentOS 7 system. Firewalld is a complete firewall solution that has been made available by default on all CentOS 7 servers. It is highly recommended that you have another firewall protecting your network or server before, or immediately after, disabling firewalld.


How to manage Firewalld ?

1. To disable firewalld, run the following command as root:

$ systemctl disable firewalld

2. To Stop Firewalld, execute the following command as root:

$ systemctl stop firewalld

3. To check the status of firewalld, run the following command as root:

$ systemctl status firewalld

Change Timezone on CentOS 7 Server - Do it Now ?

This article covers how to change timezone in CentOS 7. A time zone is basically a region of the globe that observes a uniform standard time for constitutional, business and cultural purposes.

To get detailed information your CentOS server's date, time, and timezone you use the timedatectl command:

$ timedatectl

To Delete the current /etc/localtime file or symlink:

$ sudo rm -rf /etc/localtime

Change Hostname on CentOS 7 - How to do it ?

This article covers how to change the hostname on CentOS 7 using different methods. By default, your server is started with the server's given name as the hostname. Some software such as cPanel requires a valid fully qualified domain name (FQDN) for the hostname to be used during their licensing verification system.


To Change a server's hostname:

1. Using a text editor, open the server's /etc/sysconfig/network file. The following example shows how to open this file in the GNU nano text editor:

# sudo nano /etc/sysconfig/network

2. Modify the HOSTNAME= value to match your FQDN hostname, as shown in the following example:

HOSTNAME=myserver.domain.com

3. Open the file at /etc/hosts. To update the information for internal networking, change the host that is associated with the main IP address for your server, as shown in the following example:

127.0.0.1      localhost localhost.localdomain
123.45.67.89   hostname.domain.com   hostname

4. Run the hostname command. This command enables you to change the hostname on the server that the command line remembers, but it does not actively update all of the programs that are running under the old hostname. The following code provides an example:

# hostnamectl set-hostname hostname.domain.com
# hostname
hostname.domain.com
#

5. Use the following command to restart networking on your server to ensure that changes persist on restart:

# /etc/init.d/network restart

Change the SSH Port on Ubuntu 20.04 Linux Server

This article covers how to change SSH port on your Linux system. SSH (Secure shell) is a cryptographic network protocol used to connect to a remote server securely and it transfer the data in encrypted form between the host and the client.

The default TCP port for SSH is 22, and by changing this default port to the other, it can prevent automated bots and malicious users from being brutally forced into the server.

Before changing the default SSH port number, can check the current port with the below command:

# netstat -ntlp | grep ssh


To change the SSH port:

1. Open the main SSH daemon configuration file /etc/ssh/sshd_config:

# vi /etc/ssh/sshd_config

2. Now search line begins with Port 22 and add hashtag (#) in front of that line. 

3. Then add a new Port line below with the custom port.

Note: Replace the sample port number with the custom port number that needs to be set.

4. Save and exit.


How to Restart the SSH daemon for the changes to take effect ?

Run the below commands to restart the SSH daemon and verify that the port changed:

# systemctl restart sshd
# netstat -ntlp | grep ssh

Install Git on Debian 9 System - Step by Step Process ?

This article covers how to install Git on your Debian server and how to Setting up Git. With versioning tools such as Git, you can track changes, revert to previous stages, and branch to create alternate versions of files and directories.


How to Install Git with Default Packages on Debian?

1. First, use the apt package management tools to update your local package index. 

After updating the system, you can download and install Git:

$ sudo apt update
$ sudo apt install git

2. You can confirm that you have installed Git correctly by running the following command:

git --version

Install Iptables on CentOS 7 Server - Step by Step Process ?

This article covers how to disable FirewallD and install and iptables on CentOS 7 server. The iptables service stores configuration in /etc/sysconfig/iptables and /etc/sysconfig/ip6tables , while firewalld stores it in various XML files in /usr/lib/firewalld/ and /etc/firewalld/ . 

Note that the /etc/sysconfig/iptables file does not exist as firewalld is installed by default on Red Hat Enterprise Linux.

FirewallD is a complete firewall solution that can be controlled with a command-line utility called firewall-cmd. If you are more comfortable with the Iptables command line syntax, then you can disable FirewallD and go back to the classic iptables setup.


To Install and Use Iptables Linux Firewall:

1. Connect to your server via SSH.

2. Execute the following command one by one: 

$ sudo apt-get update 
$ sudo apt-get install iptables

3. Check the status of your current iptables configuration by running:

$ sudo iptables -L -v


Location of iptables rules on CentOS ?

CentOS 7 uses FirewallD by default. If you would like to manage iptables/ip6tables rules directly without using FirewallD, you may use the old good iptables-services service which will load the iptables/ip6tables rules saved in /etc/sysconfig/iptables and /etc/sysconfig/ip6tables when it is started during boot time.

Configure Firewall with FirewallD on CentOS 7

This article covers how to configure and manage the FirewallD service on your CentOS system. A Linux firewall used to protect your workstation or server from unwanted traffic. You can set up rules to either block traffic or allow through. You can add or delete or update firewall rules without restarting the firewall daemon or service. The firewall-cmd act as a frontend for the nftables. In CentOS 8 nftables replaces iptables as the default Linux network packet filtering framework. 


To Start and enable firewalld, run the commands:

$ sudo systemctl start firewalld
$ sudo systemctl enable firewalld

To Stop and disable firewalld, run the commands:

$ sudo systemctl stop firewalld
$ sudo systemctl disable firewalld

To Check the firewalld status, run the command:

$ sudo firewall-cmd --state

To Command to reload a firewalld configuration when you make change to rules, run the command:

$ sudo firewall-cmd --reload

To Get the status of the firewalld service, run the command:

$ sudo systemctl status firewalld

Install MariaDB on CentOS 7 Server - Step by Step Process ?

This article covers how to install and Secure MariaDB on a CentOS 7 server. MariaDB is a fork of MySQL managed by the original MySQL developers. It's designed as a replacement for MySQL, uses some commands that reference mysql, and is the default package on CentOS 7.


To Install MariaDB 5.5 on CentOS 7:

1. Install the MariaDB package using the yum package manager: 

$ sudo yum install mariadb-server

2. Once the installation is complete, start the MariaDB service and enable it to start on boot using the following commands: 

$ sudo systemctl start mariadb 
$ sudo systemctl enable mariadb


To install MariaDB on CentOS 8:

1. Open the terminal application. Another option is to log in using the ssh command:

 ssh user@centos-8-server-ip

2. Install the MariaDB on CentOS 8 by running the command:

$ sudo yum install mariadb-server

3. Secure the MariaDB server in CentOS 8 by running the command:

$ sudo mysql_secure_installation

4. Finally test MariaDB installation by running the command:

$ mysql -u root -p


MariaDB vs MySQL:

Even though MariaDB is a fork of MySQL, these two database management systems are still quite different: 

MariaDB is fully GPL licensed while MySQL takes a dual-license approach.

MariaDB supports a lot of different storage engines. 

In many scenarios, MariaDB offers improved performance.

Install PHP 7.3 on Ubuntu 18.04 - Step by Step Process ?

This article covers how to install PHP 7.3 on Ubuntu 18.04 server. Also, you will learn how to configure PHP with Apache and Nginx web servers. 


How to Install PHP 7.4 on Ubuntu ?

Use the following set of commands to enable PPA for PHP 7.4 in your Ubuntu system and install it. You can use this version for production use also.

$ sudo apt-get install software-properties-common
$ sudo add-apt-repository ppa:ondrej/php
$ sudo apt-get update
$ sudo apt-get install -y php7.4

Now use the following command to check installed php version on your system.

$ php -v 


How to Install PHP 7 Modules ?

You can install the required PHP modules on your system as below command:

$ sudo apt-get install php7.2-mysql php7.2-curl php7.2-json php7.2-cgi php7.2-xsl

Secure Nginx with Let's Encrypt on Ubuntu 18.04 - How to do it ?

This article covers how to install certbot client, obtain Let's Encrypt SSL certificate and configured to Nginx to use the certificates. Also, you will learn how to set up a cronjob for automatic certificate renewal.

Let's Encrypt is a Certificate Authority (CA) that provides an easy way to obtain and install free TLS/SSL certificates, thereby enabling encrypted HTTPS on web servers. 


To Install Certbot on Ubuntu:

1. First, add the repository.

$ sudo add-apt-repository ppa:certbot/certbot

You'll need to press ENTER to accept.

2. Install Certbot's Nginx package with apt:

$ sudo apt install python-certbot-nginx

Install LEMP Stack on CentOS 7 - Step by Step Process ?

This article covers how to install LEMP stack on CentOS 7. LEMP stands for the Linux operating system, with the ENginx web server (which replaces the Apache component of a LAMP stack). The site data is stored in a MySQL-based database, and dynamic content is processed by PHP.

A LEMP software stack is basically a group of open source software that is typically installed together to enable a server to host dynamic websites and web apps.


To install Nginx on CentOS:

1. Add the CentOS 7 EPEL repository, run the following command:

$ sudo yum install epel-release

2. Now that the EPEL repository is installed on your server, install Nginx using the following yum command:

$ sudo yum install nginx

3. Once the installation is finished, start the Nginx service with:

$ sudo systemctl start nginx

Install phpMyAdmin with Nginx on CentOS 7 - Step by Step Process ?

This article covers how to install phpMyAdmin with Nginx on CentOS 7 system. phpMyAdmin helps to handle the database administration of MySQL, MariaDB and Drizzle servers over the web. It basically provides the intuitive web interface and supports most of the MySQL features to create and drop databases, create/drop/alter tables, delete/edit/add columns, execute any SQL statement and to manage indexes on columns.


To install phpMyAdmin, run the following commands:

# yum install epel-release
# yum install phpmyadmin


To restart nginx, mariadb and php-fpm services, run the following commands:

# systemctl restart mariadb.service
# systemctl restart nginx.service
# systemctl restart php-fpm.service

Install phpMyAdmin with Apache on CentOS 7 - Step by Step Process ?

This article covers how to Install phpMyAdmin with Apache on CentOS 7 system. phpMyAdmin is a database utility used for managing MySQL databases through a graphical web-based interface. It can be configured to manage a local database (on the same system), or a remote database (over a network).


To Install EPEL Repository:

1. Get access to the EPEL repository – the Extra Packages for Enterprise Linux, by running the command.

$ sudo yum install -y epel-release

2. Once that operation finishes, it's a good idea to refresh and update the EPEL repository.

$ sudo yum –y update


To Install Apache Web Server:

1. Install Apache on CentOS use the command.

$ yum install httpd -y

2. Verify the status of Apache by running with the command.

$ systemctl status httpd


To install PHPMyAdmin on CentOS, enter the command:

$ sudo yum -y install phpmyadmin

Install Nginx on Debian 9 Server - Step by Step Process ?

This article covers how to install Nginx on your Debian 9 server. Now you can deploy your applications and use Nginx as a web or proxy server. Nginx is more resource-friendly than Apache in most cases and can be used as a web server or reverse proxy.


To install Nginx on Debian:

1. Update our local package index so that we have access to the most recent package listings:

$ sudo apt update

2. We can now install nginx:

$ sudo apt install nginx

When prompted to confirm the installation, hit Enter to proceed. After that, apt will install Nginx and any required dependencies to your server.


Profiles available for Nginx:

  • Nginx Full: This profile opens both port 80 (normal, unencrypted web traffic) and port 443 (TLS/SSL encrypted traffic).
  • Nginx HTTP: This profile opens only port 80 (normal, unencrypted web traffic).
  • Nginx HTTPS: This profile opens only port 443 (TLS/SSL encrypted traffic).

Secure Nginx with Let's Encrypt on CentOS 7 - How to do it ?

This article covers how to use the certbot Let’s Encrypt client to obtain a free SSL certificate and use it with Nginx on CentOS 7. 

Let's Encrypt is a new Certificate Authority (CA) that provides an easy way to obtain and install free TLS/SSL certificates, thereby enabling encrypted HTTPS on web servers. It simplifies the process by providing a software client, Certbot, that attempts to automate most (if not all) of the required steps. 

Currently, the entire process of obtaining and installing a certificate is fully automated on both Apache and Nginx web servers.


To Install the Certbot Let's Encrypt Client:

1. Enable access to the EPEL repository on your server by typing:

$ sudo yum install epel-release

2. Once the repository has been enabled, you can obtain the certbot-nginx package by typing:

$ sudo yum install certbot-nginx


How to Install Nginx on CentOS ?

1. To install Nginx, run the command:

$ sudo yum install nginx

2. Then, start Nginx using systemctl:

$ sudo systemctl start nginx


How to configure firewall on CentOS ?

If you have a firewall enabled, make sure port 80 and 443 are open to incoming traffic.

1. If you have a firewalld firewall running, you can open these ports by typing:

$ sudo firewall-cmd --add-service=http
$ sudo firewall-cmd --add-service=https
$ sudo firewall-cmd --runtime-to-permanent

2. If have an iptables firewall running, the commands you need to run are highly dependent on your current rule set. For a basic rule set, you can add HTTP and HTTPS access by typing:

$ sudo iptables -I INPUT -p tcp -m tcp --dport 80 -j ACCEPT
$ sudo iptables -I INPUT -p tcp -m tcp --dport 443 -j ACCEPT

Configure Nginx Server Blocks on CentOS 7 - Step by Step Process ?

This article covers how to create an Nginx server block configuration to host multiple website on a single CentOS server.

Server Blocks, often referred to as Nginx virtual host are a feature of the Nginx web server that allows you to host multiple websites on one server.

To Test NGINX configuration file, run the command:

$ sudo nginx --t

If the syntax is OK, the output tells you the test was successful.


To restart your Nginx web server and confirm that it's running as expected:

$ sudo systemctl restart nginx
$ sudo systemctl status Nginx


To Enable HTTPS on Domain Hosted on Nginx:

You may consider encrypting your domain using Lets Encrypt SSL to add a layer of protection and secure traffic to and from the webserver:

$ sudo dnf install certbot python3-certbot-nginx
$ sudo certbot --nginx

Install Nginx on CentOS 7 Server - Step by Step Process ?

This article covers how to Install and configure Nginx on your CentOS 7 server. Now you can deploy your applications and use Nginx as a web or proxy server. 

Nginx is a high performance web server software. It is a much more flexible and lightweight program than Apache HTTP Server.


To Install Nginx Web Server on CentOS 8:

1. Install the nginx package with:

$ sudo dnf install nginx

When prompted, enter y to confirm that you want to install nginx. After that, dnf will install Nginx and any required dependencies to your server.

2. After the installation is finished, run the following commands to enable and start the server:

$ sudo systemctl enable nginx
$ sudo systemctl start nginx

This will make Nginx start at system boot.


To configure Firewall Rules on CentOS for Nginx:

1. Run the following command to permanently enable HTTP connections on port 80:

$ sudo firewall-cmd --permanent --add-service=http

2. To verify that the http firewall service was added correctly, you can run:

$ sudo firewall-cmd --permanent --list-all

3. To apply the changes, you'll need to reload the firewall service:

$ sudo firewall-cmd --reload

Secure Apache with Let's Encrypt on CentOS 7 - Step by Step Process ?

This article covers how to secure Apache with Let's Encrypt SSL on CentOS 7 using Certbot client. Also, you will learn how to set up a cronjob for automatic certificate renewal. Basically, A security certificate is critical for securing traffic sent from web browsers to web servers. Let's Encrypt certificate is a free, open and automated certificate authority that you can use to encrypt your site. The certificate expires after every 90 days and auto-renews at absolutely no cost.


To Install Certbot in CentOS 8.

Certbot is a client that automates the installation of the security certificate. It fetches the certificate from Let's encrypt authority and deploys it on your web server without much of a hassle.

1. Before downloading certbot, first, install packages that are necessary for the configuration of an encrypted connection:

$ sudo dnf install mod_ssl openssl

2. Download certbot using the curl command:

$ sudo curl -O https://dl.eff.org/certbot-auto

3. Next, move the certbot file to the /usr/local/bin directory and assign the execute file permissions:

$ sudo mv certbot-auto /usr/local/bin
$ sudo chmod 755 /usr/local/bin/certbot-auto


To Assign the permissions to the Document root of a domain:

$ sudo chown -R apache:apache /var/www/domain.com

For the changes to come into effect, restart the Apache service:

$ sudo systemctl restart httpd

Install MySQL on CentOS 7 Server - Step by Step Process ?

This article covers how to install and secure a MySQL server on a CentOS 7 server. MySQL is one of the most widely used database management systems for websites and server applications.


To start the MySQL server daemon with the following command:

$ sudo systemctl start mysqld

systemctl doesn't display the outcome of all service management commands, so to be sure we succeeded, we'll use the following command:

$ sudo systemctl status mysqld

To configure MySQL, run the following command:

$ sudo mysql_secure_installation

To Current MySQL Version, run the command:

$ mysql -u root -p


Terms used in Managing MySQL User Permissions:

  • SELECT – users can read through the database using the select command.
  • CREATE – they can generate new tables.
  • DROP – allows users to remove tables.
  • DELETE – users can take out rows from tables.
  • INSERT – lets users add in rows into tables.
  • UPDATE – enable them to update the rows.
  • GRANT OPTION – they can grant or remove the privileges of other users.

Configure Apache Virtual Hosts on CentOS 7

This article covers method to easily configure Apache virtual hosts. You repeat same procedure for multiple domain.

You can use yum to install Apache through CentOS's default software repositories:

$ sudo yum -y install httpd

Next, enable Apache as a CentOS service so that it will automatically start after a reboot:

$ sudo systemctl enable httpd.service


How to Set Up Local Hosts File ?

If you are on a Mac or Linux computer, edit your local hosts file with administrative privileges by typing:

$ sudo nano /etc/hosts

The details that you need to add are the public IP address of your VPS followed by the domain that you want to use to reach that VPS:

127.0.0.1   localhost
127.0.1.1   guest-desktop
server_ip_address example.com
server_ip_address example2.com

This will direct any requests for example.com and example2.com on our local computer and send them to our server at server_ip_address.

Install PHP 7.4, 7.3, 7.2, 7.1 on CentOS 7 & CentOS 8 - Step by Step Process ?

This article covers how to install specific version of PHP 7 on CentOS 7 Linux server. PHP is a programming language often used to automate server tasks. It is part of the LAMP (Linux, Apache, MySQL, PHP) stack, which is a bundle of software used for running internet servers and services. PHP handles dynamic content, database requests, and processing and displaying data.


To Verify PHP Version:

You can Check which version of PHP you are running with the command:

$ php –v


To Install PHP with Apache on CentOS:

1. Start by installing the yum-utils package by entering the following command in a terminal window:

$ sudo yum install yum-utils –y

2. Then, enable the epel-release repository by entering the following:

$ sudo yum install epel-release –y

3. Finally, add the following software repositories that contain the PHP packages:

$ sudo yum install http://rpms.remirepo.net/enterprise/remi-release-7.rpm

4. For PHP 7.3, you can enable PHP 7.3. Install the release with the following commands:

$ sudo yum-config-manager ––enable remi–php73
$ sudo yum install php php-common php-opcache php-mcrypt php-cli php-gd php-curl php-mysql –y

Install Apache on CentOS 7 Server - Step by Step Process ?

This article covers how to install Apache on your CentOS 7 system. You can now ready to start deploying your applications and use Apache as a web server.

Basically, The Apache HTTP server is the most widely-used web server in the world. It provides many powerful features including dynamically loadable modules, robust media support, and extensive integration with other popular software.


To Install Apache on CentOS:

1. Update the local Apache httpd package index to reflect the latest upstream changes:

$ sudo yum update httpd

2. Once the packages are updated, install the Apache package:

$ sudo yum install httpd

3. Enable firewalld's http service with the following command:

$ sudo firewall-cmd --permanent --add-service=http

4. Configure Apache to serve content over HTTPS, you will also want to open up port 443 by enabling the https service:

$ sudo firewall-cmd --permanent --add-service=https

5. Finally, reload the firewall to put these new rules into effect:

$ sudo firewall-cmd --reload

Create a Sudo User on CentOS - How to do it ?

This article covers how to create a user with sudo privileges. You can now log in to your CentOS server with this user account and use sudo to run administrative commands.

Performing server administration as a non-root user is a best practice.

For security, your first task when deploying a CentOS instance is to create a non-root user with sudo access.


How to Add a New User Account on CentOS Linux System ?

1. To Create a new user account with the adduser command:

# adduser example_user

2. Set a strong password for the new user (new_user) with passwd.

# passwd new_user

Install Go on Linux Mint 20 - Step by Step Process ?

This article covers the installation procedure of Go language on a Linux Mint 20 system. Also, we dealt with an easy way to remove Go language from a Linux Mint 20 system.

To Verify Go Language Installation, run the command:

$ go version 


Features of Go Programming

  • Statically type and compiled programming language.
  • Concurrency support and Garbage collection.
  • Strong library and toolset.
  • Multiprocessing and High-performance networking.
  • Known for readability and usability (Like Python).

Install WordPress with Nginx on Ubuntu 20.04 LTS - Step by Step Process ?

This article covers how to install WordPress on Ubuntu 20.04 with Nginx HTTP Server and Let's Encrypt wildcard SSL Certificates. WordPress is a free, open-source, and most popular content management system that allows you to create a blog on the Internet.


You can install nginx, MariaDB, PHP and all the required PHP extensions with the following command:

$ apt-get install nginx mariadb-server php php-curl php-mysql php-gd php-intl php-mbstring php-soap php-xml php-xmlrpc php-zip php-fpm -y

Once the LEMP server is installed, start the Nginx and MariaDB service with the following command:

$ systemctl start nginx
$ systemctl start mariadb


Nginx's inbuilt features includes:

  • Nginx is built to work on low memory usage.
  • It can support extremely high concurrency.
  • Is Ipv6 enabled.
  • Supports reverse proxy with efficient caching.
  • Provides an inbuilt load balancer.
  • Supports WebSockets.
  • Optimized handling of index files, static files and provides auto indexing.
  • Is accompanied with FastCGI for efficient caching.

Create a Sudo User on Ubuntu 20.04 - Step by Step Process ?

This article covers how to create a user with sudo privileges. You can now log in to your Ubuntu server with this user account and use sudo to run administrative commands.

Basically, The sudo command provides a mechanism for granting administrator privileges, ordinarily only available to the root user, to normal users. 

Install and Configure Memcached on CentOS 8 - Step by Step Process ?

This article covers how to install and configure the Memcached caching server on CentOS 8 system through the command-line tool.

Now, you can easily install and configure the Memcached server on your CentOS 8 system easily. 

Memcached is a free and open-source high-performance in-memory key-value data store.

Typically, it used as a caching system to speed up applications by caching various objects from the results of database calls.


To install memcached on CentOS, perform the following tasks as a user with root privileges:

1. Install memcached and its dependencies:

$ yum -y update
$ yum install -y libevent libevent-devel
$ yum install -y memcached
$ yum install -y php-pecl-memcache

2. Change the memcached configuration setting for CACHESIZE and OPTIONS:

i. Open /etc/sysconfig/memcached in a text editor.

ii. Locate the value for CACHESIZE and change it to at least 1GB. For example

CACHESIZE="1GB"

iii. Locate the value for OPTIONS and change it to localhost or 127.0.0.1

3. Save your changes to memcached and exit the text editor.

4. Restart memcached.

$ service memcached restart

5. Restart your web server.

For Apache:

$ service httpd restart

Install Moodle on Red Hat Enterprise Linux 8 - Step by Step Process ?

This article covers how to download, configure, and install Moodle powered by the LAMP stack on RHEL 8.

Moodle is the world’s most popular learning management system for building robust online learning sites.

How to open HTTP and HTTPS for Moodle Learning Platform in CentOS 8 ?
To open HTTP and HTTPS services in the firewall to allow traffic to the NGINX web server, run the commands below:

# firewall-cmd --permanent --zone=public --add-service=http 
# firewall-cmd --permanent --zone=public --add-service=https

# firewall-cmd --reload

Setup Xrdp over Xorg in CentOS Linux System with Multi Sessions

This article covers how to run Xrdp over Xorg protocol, which far most secure and recommended over the XVNC protocols.
Also, we covered the sessions manager that how you can manage your remote connections by tweaking its configuration parameters which sometimes come in a challenging phase.

Install Tig on Ubuntu 20.04 - Step by Step Process ?

This article covers how to install Tig on your Ubuntu 20.04 system and hence interacting with Git all the more efficiently.
However, you can get rid of this utility any time you want by following the uninstallation procedure that we have shared with you in this guide.
Tig is a text-mode interface for git. It mainly serves as a Git repository browser. It can also assist in staging changes for commit at the chunk level.

Features of Tig:
1. Browses the commits in the current branch
2. Displays the commits for one or more specific branches
3. Compares two branches
4. Helps to see the changes for a single file
5. Displays the list of stashes
6. Shows references for branches, tags and remotes

To install tig on Ubuntu:
1. First update the system, run:

# sudo apt update

2. To install tig on ubuntu, run:

# sudo apt install tig


To uninstall tig on Ubuntu:
To completely remove tig from your Ubuntu machine, type;

# sudo apt remove tig -y

Install Amazon Web Service CLI on Linux Mint 20 - Step by Step Process ?

This article covers how to install the AWS CLI very conveniently on your Linux Mint 20 system and use it for managing the Amazon Web Services very efficiently.
The AWS or Amazon Web Service command line interface is a command line tool for manage our Amazon web services.
AWS CLI provides direct access to the Amazon Web Services public API.
As it is a command line tool, it can also be used to create scripts to automate your Amazon web services.

To the AWS CLI on Ubuntu With APT:
1. First we update the package listing cache with the following command in the terminal (Ctrl + Alt + T):

# sudo apt-get update

2. Now we are going to install the AWS CLI using the command:

# sudo apt-get install awscli

3. We will can check if AWS CLI is working correctly with the following command:

# aws --version

Install Node.js on CentOS 8 - Step by Step Process ?

This article covers the different methods to perform the installation of NodeJS on the CentOS 8 system.

Now that NodeJS is installed on your CentOS 8 system, you can use it to deploy a NodeJS application on the system.
Node.js is a cross-platform, runtime environment that was built on Chrome's JavaScript. This environment is designed to execute JavaScript code on the server-side.

To check Node version number, run the command:

# node --version

Set up passwordless SSH Authentication on Linux - Step by Step Process ?

This article covers how to setup an SSH key-based authentication as well how to connect to your Linux server without entering a password.
To set up a passwordless SSH login in Linux all you need to do is to generate a public authentication key and append it to the remote hosts ~/.ssh/authorized_keys file.

To Disable SSH Password Authentication
To add an extra layer of security to your server you can disable the password authentication for SSH.
Before disabling the SSH password authentication make sure you can log in to your server without a password and the user you are logging in with has sudo privileges.
The following steps describe how to configure sudo access:
1. Log into your remote server with SSH keys, either as a user with sudo privileges or root:

# ssh sudo_user@server_ip_address

2. Open the SSH configuration file /etc/ssh/sshd_config, search for the following directives and modify as it follows:

/etc/ssh/sshd_config
PasswordAuthentication no
ChallengeResponseAuthentication no
UsePAM no

3. Once you are done save the file and restart the SSH service.
On Ubuntu or Debian servers, run the following command:

# sudo systemctl restart ssh

On CentOS or Fedora servers, run the following command:

# sudo systemctl restart sshd

Install Atom editor on CentOS 8 - Step by Step Process ?

This article covers how to install atom editor on CentOS 8 using the command-line application.

Atom is a free and open-source text and source code editor for OS X, Linux, and Windows with support for plug-ins written in Node.js, and embedded Git Control, developed by GitHub

To install latest version of Atom using .rpm package on your CentOS 8 machine:
1. First, go to the Atom official website and download the Atom .rpm package:

# sudo curl -SLo atom.x86_64.rpm  https://atom.io/download/rpm

2. You can now install Atom using dnf command:

# sudo dnf localinstall atom.x86_64.rpm

3. Now that Atom is installed on your CentOS system you can launch it from the command line by typing atom or by clicking on the Atom icon (Applications -> Programming -> Atom).

Install Gradle on CentOS 8 - Step by Step Process ?

This article covers how to install the latest Gradle version on CentOS 8 system. 

Also you will learn how to set up the environment variable in the Gradle configuration file.

Gradle is an open-source build automation system.

It supports multiple programming languages such as Java, C++, and Python development. It is based on the concepts of Apache Ant and Apache Maven.


To verify if Gradle is installed properly use the gradle -v command which will display the Gradle version:

# gradle -v


Install RPM Packages on CentOS 8 - Step by Step Process ?

This article covers how to install the RPM package on the CentOS 8 system.

Now you can easily download, install, update and erase Rpm packages on your CentOS system.
While working in Linux, you may have seen downloadable files with the .rpm extension.
Rpm files are designed to be downloaded and installed independently, outside of a software repository.
RPM Package Manager (RPM) is a free and open-source package management system for installing, uninstalling and managing software packages in Linux.

How to Download RPM Installation File on Linux ?
1. To install wget in CentOS, enter the following in a terminal window:

$ sudo yum install wget

2. To install weget in Fedora, enter the following:

$ sudo dnf install wget

3. Now, you can use the wget command to download the .rpm file you want.

Enter the following:

$ wget http://some_website/sample_file.rpm


To check the .rpm file for dependencies using the following command:

# sudo rpm –qpR sample_file.rpm

The system should list all the dependencies:
i. –q – This option tells RPM to query the file
ii. –p – This option lets you specify the target package to query
iii. –R – This lists the requirements for the package


How to install a .rpm file to your Linux CentOS or Fedora system ?
You can use the yum package manager to install .rpm files.
Enter the following:

# sudo yum localinstall sample_file.rpm

The localinstall option instructions yum to look at your current working directory for the installation file.

Install Flameshot on CentOS 8 - Step by Step Process ?

This article covers how to install the flameshot application on CentOS 8.

You will also learn how you can remove it from your CentOS 8 if you don’t need more on your system.

Main features of flameshot includes:
1. Supports graphical and CLI mode.
2. Edit images instantly.
3. Image uploads to Imgur.
4. Export and import configuration.
5. Easy to use and customizable.

To Install Flameshot in Linux:
Flameshot can be installed using package managers. Before installing through this method make sure you verify the version that ships with your OS:

$ sudo dnf install flameshot  # Rhel, Centos, Fedora
$ sudo apt install flameshot  # Debian, Ubuntu-based distro 

OR
# Ubuntu based distribution

$ wget https://github.com/flameshot-org/flameshot/releases/download/v0.9.0/flameshot-0.9.0-1.ubuntu-20.04.amd64.deb
$ dpkg -i flameshot-0.9.0-1.ubuntu-20.04.amd64.deb

# Rhel based distribution

$ wget https://github.com/flameshot-org/flameshot/releases/download/v0.9.0/flameshot-0.9.0-1.fc32.x86_64.rpm
$ rpm -i flameshot-0.9.0-1.fc32.x86_64.rpm

Change Sudo Password Timeout on Ubuntu 20.04 LTS - How to do it ?

This article covers how you can easily change the sudo password timeout by adding a single entry in the sudoers file. If you are using Vi instead of Nano, follow the instructions described here.
You use sudo for some command in the terminal, it asks for the password.

You enter the password, the command runs.
For the subsequent commands, even if they need superuser privileges, you don't need to enter the password again.
After a certain amount of time, when you try to use sudo, it asks for the password again.
It happens because there is a default timeout in Ubuntu and other Linux system for Sudo. In Ubuntu, this default sudo timeout is 15 minutes.
If you think 15 minute is too short or too long you can even change the sudo password timeout in Ubuntu.

To Change sudo password timeout in Ubuntu:
1. Open a terminal (Ctrl+Alt+T) and use the following command:

$ sudo visudo

It will open a file in nano text editor that contains some settings related to sudo.
In here look for the following line:

Defaults        env_reset

Replace above line with this one:

Defaults        env_reset, timestamp_timeout=XX

Where XX is the new timeout value in minutes.
Of course you have to replace the XX with the desired timeout value.
2. Once you are done changing the default sudo password timeout, use Ctrl+X to exit the editor.
It will give you option to save or cancel the changes.

Use Y to save the changes.

Install Visual Studio Code on CentOS 8 - Step by Step Process ?

This article covers how to install the VS code package on CentOS 8 using the command line application. Visual Studio Code is a free and open-source, cross-platform IDE or code editor that enables developers to develop applications and write code using a myriad of programming languages such as C, C++, Python, Go and Java to mention a few.


To Install Visual Studio Code on Debian, Ubuntu and Linux Mint:

1. Update your system by running the command.

$ sudo apt update

2. Once updated, proceed and install dependencies required by executing.

$ sudo apt install software-properties-common apt-transport-https

3. Next, using the wget command, download the repository and import Microsoft’s GPG key as shown:

$ wget -qO- https://packages.microsoft.com/keys/microsoft.asc | gpg --dearmor > packages.microsoft.gpg
$ sudo install -o root -g root -m 644 packages.microsoft.gpg /etc/apt/trusted.gpg.d/
$ sudo sh -c 'echo "deb [arch=amd64 signed-by=/etc/apt/trusted.gpg.d/packages.microsoft.gpg] https://packages.microsoft.com/repos/vscode stable main" > /etc/apt/sources.list.d/vscode.list'

4. Once you’ve enabled the repository, update the system and install Visual Studio Code by running the command:

$ sudo apt update
$ sudo apt install code

Install CouchDB on CentOS 8 - Step by Step Process ?

This article covers CouchDB installation on CentOS Linux System. 

Apache CouchDB is an open-source database management system, developed by Apache Software Foundation. It is a NoSQL document-store database developed in ErLang.

CouchDB uses multiple formats and protocols to store, transfer, and process its data, it uses JSON (JavaScript Object Notation) to store data, JavaScript as its query language using MapReduce, and HTTP for an API.

Unlike a relational database, a CouchDB database does not store data and relationships in tables. Instead, each database is a collection of independent documents. Each document maintains its own data and self-contained schema.

CouchDB software includes a native web interface i.e. Fauxton for administration of CouchDB database server.


To Install CouchDB Yum Repository on CentOS 8:

1. Create a repo file by using vim editor.

# vi /etc/yum.repos.d/bintray-apache-couchdb-rpm.repo

2. And add following directives in this file.

[bintray--apache-couchdb-rpm]
name=bintray--apache-couchdb-rpm
baseurl=http://apache.bintray.com/couchdb-rpm/el$releasever/$basearch/
gpgcheck=0
repo_gpgcheck=0
enabled=1

3. Build cache for newly installed yum repositories.

# dnf makecache

4. Now we can install CouchDB software by using dnf command.

# dnf install -y couchdb

Install Ansible on Ubuntu 20.04 LTS - Step by Step Process ?

This article covers how to install and configure Ansible on Ubuntu 20.04. Ansible is a widely used automation tool in DevOps and used by thousands of developers and sysadmins to configure and deploy applications on servers.

It saves time and minimizes the effort required to handle a multitude of servers in a complex IT infrastructure. 


To install Ansible on Ubuntu:

1. First, refresh your system’s package index with:

# sudo apt update

2. Following this update, you can install the Ansible software with:

$ sudo apt install ansible

Press Y when prompted to confirm installation.


To check if Ansible is able to connect to these servers and run commands via SSH:

From your local machine or Ansible control node, run:

$ ansible all -m ping -u root

This command will use Ansible's built-in ping module to run a connectivity test on all nodes from your default inventory, connecting as root.

The ping module will test:

i. if hosts are accessible;

ii. if you have valid SSH credentials;

iii. if hosts are able to run Ansible modules using Python.

Install Mono on CentOS 8 - Step by Step Process ?

This article covers how to install and use Mono on CentOS 8 system. Mono is a platform for developing and running cross-platform applications based on the ECMA/ISO Standards. 

It is a free and open-source implementation of Microsoft’s .NET framework.


To Verify the installation by running the following command that prints the Mono version:

$ mono --version

Install and Configure Fail2ban on Red Hat Enterprise Linux 8 - Step by Step Process ?

This article covers the installation of Fail2ban and the configuration of an sshd filter. There are so many options to configure but we focused on the basic ones. Feel free to peruse the Fail2ban man pages by running man fail2ban to discover what more you can do with it.

Fail2ban is a free, open-source and widely used intrusion prevention tool that scans log files for IP addresses that show malicious signs such as too many password failures, and much more, and it bans them (updates firewall rules to reject the IP addresses). 

By default, it ships with filters for various services including sshd.


To install  and configure Fail2ban on CentOS/RHEL 8:

1. After logging into your system, access a command-line interface, then enable the EPEL repository on your system:

# dnf install epel-release

OR

# dnf install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm

2. Afterward, install the Fail2ban package by running the following command:

# dnf install fail2ban

3. To start and enable the fail2ban service for now and check if it is up and running using the following systemctl command:

# systemctl start fail2ban
# systemctl enable fail2ban
# systemctl status fail2ban

Install LAMP Stack on Red Hat Enterprise Linux 8 - Step by Step Process ?

This article covers the installation of the LAMP stack (i.e., Linux, Apache, MariaDB, and PHP) on RHEL 8.

LAMP stands for Linux, Apache, MariaDB/MySQL and PHP, all of which are open source.


With the yum commands below, install LAMP stack:

# Will automatically update

$ sudo yum -y update

# Will automatically install Apache/HTTPD

$ sudo yum -y install httpd


To Install MariaDB Database Server on CentOS 8/RHEL 8:

1. Enter the following command to install MariaDB on CentOS 8/RHEL 8.

# dnf install mariadb-server mariadb -y

2. After it's installed, we need to start it.

# systemctl start mariadb

3. Enable auto start at system boot time.

# systemctl enable mariadb

4. Check status:

# systemctl status mariadb

Install and Use Docker Compose on CentOS 8 - Step by Step Process ?

This article covers how to install and use the Docker-compose on CentOS 8 system. By using the Docker-compose, you can deploy multiple Docker applications with container services through a single command. 

Basically, Docker Compose is a tool that can be used to define and run multiple containers as a single service. With Docker Compose, you can link multiple containers and deploy an application from a single command. 

It is mainly used in the development, testing and staging environment. 

Docker Compose uses a YAML file to define a complex stack in a file and running it with a single command.


To install Docker on CentOS:

1. Before starting, make sure you have Docker installed on your server. If not installed, you will need to add Docker-CE repository to your system. 

You can add it with the following command:

$ dnf config-manager --add-repo=https://download.docker.com/linux/centos/docker-ce.repo

2. Once the repository is added, install the latest version of docker using the following command:

# dnf install docker-ce --nobest -y
# systemctl start docker
# systemctl enable docker

3. You can verify the docker version with the following command:

$ docker --version

Add a User to Sudoers on Ubuntu 20.04 LTS - Step by Step Process ?

This article covers how to add a user to sudoers using different methods, limit root access with sudo and remove a user from sudoers.

Sudo is a very handy tool for system administrators that allow them to provide root access to a user with granularity.


Steps to Add Sudo User on Ubuntu ?

1. Log into the system with a root user or an account with sudo privileges.

2. Open a terminal window and add a new user with the command:

# adduser newuser

The adduser command creates a new user, plus a group and home directory for that user.

You may get an error message that you have insufficient privileges. (This typically only happens for non-root users.) Get around it by entering:

# sudo adduser newuser

3. You can replace newuser with any username you wish. The system will add the new user; then prompt you to enter a password. Enter a great secure password, then retype it to confirm.


To Add User to Sudo Group:

1. In a terminal, enter the command:

# usermod -aG sudo newuser

Replace newuser with the username that you entered in Step 1.

Again, if you get an error, run the command with sudo as follows:

# sudo usermod -aG sudo newuser

The -aG option tells the system to append the user to the specified group. (The -a option is only used with G).

Install Apache OpenOffice on CentOS 8 - Step by Step Process ?

This article covers how to install Apache OpenOffice on CentOS 8. Apache OpenOffice is a software bundle which contains various software tools like word processor, spreadsheet, database management, and so on. It is very much similar to other popular editors like Libreoffice and NeoOffice. 


Main features and tools provided by OpenOffice:

1. Writer a word processor you can use for anything from writing a quick letter to producing an entire book.

2. Calc a powerful spreadsheet with all the tools you need to calculate, analyze, and present your data in numerical reports or sizzling graphics.

3. Impress the fastest, most powerful way to create effective multimedia presentations.

4. Draw lets you produce everything from simple diagrams to dynamic 3D illustrations.

5. Base lets you manipulate databases seamlessly. Create and modify tables, forms, queries, and reports, all from within Apache OpenOffice.

6. Math lets you create mathematical equations with a graphic user interface or by directly typing your formulas into the equation editor.

Install MongoDB on CentOS 8 - Step by Step Process ?

This article covers MongoDB installation on CentOS 8 system.

Instead, it uses JSON-like documents with dynamic schemas, meaning that, unlike relational databases, MongoDB does not require a predefined schema before you add data to a database. 

You can alter the schema at any time and as often as is necessary without having to set up a new database with an updated schema.


How to Start the MongoDB Service and Test the Database on Ubuntu?

1. Run the following systemctl command to start the MongoDB service:

# sudo systemctl start mongod

2. Then check the service's status:

# sudo systemctl status mongod

This command will return output like the following, indicating that the service is up and running

3. After confirming that the service is running as expected, enable the MongoDB service to start up at boot:

# sudo systemctl enable mongod


How to Managing the MongoDB Service on Ubuntu?

1. The systemctl status command checks the status of the MongoDB service:

# sudo systemctl status mongod

2. You can stop the service anytime by typing:

# sudo systemctl stop mongod

3. To start the service when it’s stopped, run:

# sudo systemctl start mongod

4. You can also restart the server when it’s already running:

# sudo systemctl restart mongod

5. If you ever wish to disable this automatic startup, type:

# sudo systemctl disable mongod

6. Then to re-enable it to start up at boot, run the enable command again:

# sudo systemctl enable mongod

Install Docker CE on CentOS 8 - Step by Step Process ?

This article covers how to perform Docker installation and Configuration. Also, you will learn how to install Docker CE on the CentOS 8 system. Docker container technology allows you to run applications in a specific and isolated environment.

Docker Community Edition (CE) is the new name for the free Docker product.

To Install Docker CE on Linux:
1. Remove all existing docker applications (that might currently be installed) in order to make sure we are using a clean installation.:

# yum remove docker docker-client docker-client-latest docker-common docker-latest docker-latest-logrotate docker-logrotate docker-engine

2. Add an external repository that will help us obtain the Docker software:

# dnf config-manager --add-repo=https://download.docker.com/linux/centos/docker-ce.repo

3. Check what versions of docker we have in the repository:

# dnf list docker-ce

4. Install the version that best matches our CentOS server version:

# dnf install docker-ce --nobest

5. We can double-check if the installation was successful by using the version command:

# docker -v

Install Gitlab on CentOS 8 - Step by Step Process ?

This article covers how  to setup Gitlab on CentOS Linux.

Gitlab is an application tool that is used for source code management. It allows you to plan your development process; code, and verify; package software, and release it with an in-built continuous delivery feature; automate configurations management, and monitor software performance.


To be able to access the GitLab interface you'll need to open ports 80 and 443. 

To do so run the following commands:

$ sudo firewall-cmd --permanent --zone=public --add-service=http
$ sudo firewall-cmd --permanent --zone=public --add-service=https
$ sudo firewall-cmd --reload



To install Postfix service to send notification emails, and enable it to start at system boot, then check if it is up and running using following commands:

# yum install postfix
# systemctl start postfix
# systemctl enable postfix
# systemctl status postfix

Install Netdata Monitoring Tool on Ubuntu 20.04 - Step by Step Process ?

This article covers how to install and configure Netdata on Ubuntu 20.04 LTS and different metrics visualized in it. Netdata provides an excellent solution for monitoring your single node in real-time. You can configure alarms and notifications which can be triggered when a certain event or threshold is exceeded.


To install Netdata on Ubuntu:

1. You can install netdata on Ubuntu by running the following commands.

$ sudo apt update 
$ sudo apt install netdata 

Press 'y' if confirmation prompted by the installer.

2. Edit netdata configuration file in your favorite text editor.

$ sudo vim /etc/netdata/netdata.conf 

3. After modifying its configuration file, you can Save your file and restart netdata service:

$ sudo systemctl restart netdata 

Install MySQL Version 8 on Red Hat Enterprise Linux 8 - Step by Step Process ?

This article covers how to Install MySQL Version 8 on Red Hat Enterprise Linux 8. Now, you should now have a fully functioning MySQL server version 8 running on your Server.


To Install MySQL 8.0 On CentOS 8 / RHEL 8:

1. Install MySQL 8.0 from MySQL Dev Community

Add the official repository of MySQL to install the MySQL community server:

$ rpm -ivh https://dev.mysql.com/get/mysql80-community-release-el8-1.noarch.rpm

Make sure the MySQL repository has been added and enabled by using the following command:

$ yum repolist all | grep mysql | grep enabled


To Manage MySQL server Service on Linux:

1. After the installation of MySQL, start MySQL server service using the following command:

$ systemctl start mysqld

2. The below command will Enable MySQL server at system startup:

$ systemctl enable mysqld

3. Verify that MySQL server is started using the following command:

$ systemctl status mysqld

Manage Firewall Rules with UFW on Red Hat Enterprise Linux 8

This article covers how to secure Red Hat Enterprise Linux 8 with UFW. UFW may not be intended to provide complete firewall functionality, but it does provide an easy way to create and manage simple firewall rules.

A firewall is a way to protect machines from any unwanted traffic from outside. 

It enables users to control incoming network traffic on host machines by defining a set of firewall rules. 

These rules are used to sort the incoming traffic and either block it or allow through.

Note that firewalld with nftables backend does not support passing custom nftables rules to firewalld, using the --direct option.


How to start, stop, restart firewalld service on an RHEL 8?

By now you know about firewalld zones, services, and how to view the defaults. It is time to activate and configure our firewall.

1. Start and enable firewalld

$ sudo systemctl start firewalld
$ sudo systemctl enable firewalld

2. Stop and disable firewalld

$ sudo systemctl stop firewalld
$ sudo systemctl disable firewalld

3. Check the firewalld status

$ sudo firewall-cmd --state

4. Command to reload a firewalld configuration when you make change to rules

$ sudo firewall-cmd --reload

5. Get the status of the firewalld service

$ sudo systemctl status firewalld


When to use firewalld, nftables, or iptables:

1. firewalld: Use the firewalld utility for simple firewall use cases. The utility is easy to use and covers the typical use cases for these scenarios.

2. nftables: Use the nftables utility to set up complex and performance critical firewalls, such as for a whole network.

3. iptables: The iptables utility on Red Hat Enterprise Linux 8 uses the nf_tables kernel API instead of the legacy back end. 

The nf_tables API provides backward compatibility so that scripts that use iptables commands still work on Red Hat Enterprise Linux 8. For new firewall scripts, Red Hat recommends to use nftables.

Install LibreOffice on CentOS 8 - Step by Step Process ?

This article covers LibreOffice installation on CentOS 8 distribution. LibreOffice is a powerful and open-source office suite that can be used on Linux, Mac as well as on Windows.

It provides various features such as word documentation, spreadsheets, data processing, drawing, presentation design, Math calculation, and more.


How to uninstall Old LibreOffice or OpenOffice Versions ?

If any previously installed LibreOffice or OpenOffice versions you have, remove it using following command.

# yum remove openoffice* libreoffice* [on RedHat based Systems]
$ sudo apt-get remove openoffice* libreoffice*	[On Debian based Systems]

Install VirtualBox on CentOS 8 - Step by Step Process ?

This article covers the complete installation guide of VirtualBox on the CentOS 8 system.

Oracle VirtualBox is a virtualization software solution that allows you to create and run virtual machines on a single hardware machine.

With VirtualBox, your existing operating system stays unaffected by the virtual environment.


To Start VirtualBox on Linux:

Use the command:

$ VirtualBox

The VirtualBox manager interface will prompt you.

Alternatively, you can use the graphical interface and access the application:

Application >> System Tools >> Oracle VM VirtualBox

Flush DNS Cache on Ubuntu 20.04 - Step by Step process ?

This article covers how to flush the DNS cache on Ubuntu. If the sites are not loading properly or you are receiving outdated sites, try to flush the DNS cache to see if the issue resolves. 

Remember, after the DNS cache is flushed, sites will first load slightly slower. 

But once the DNS cache is re-populated, sites will be loaded faster.


Facts about flushing DNS cache on Ubuntu:

1. DNS cache is a temporary database that stores information about previous DNS lookups. 

2. Whenever you visit a website, your OS and web browser will keep a record for the domain and the corresponding IP address. 

3. Flushing DNS cache eliminates the need for repetitive queries to the remote DNS servers and allows your OS or browser to resolve the website's URL quickly.


How to use dns-clean to flush DNS-Cache ?

You can clear the DNS cache is by starting the dns-clean utility. Run the following command in your Terminal to do so:

$ sudo /etc/init.d/dns-clean start

Install Cockpit on Ubuntu 20.04 - Step by step process to do this ?

This article covers how to install Cockpit on Ubuntu 20.04 system. Cockpit is a free and open source web console tool for Linux administrators and used for day to day administrative and operations tasks. 


To Install the Cockpit package on Ubuntu 20.04 LTS Server, run the command:

$ sudo apt update
$ sudo apt install cockpit -y

Once cockpit package is installed successfully then start its service using the following systemctl command,

$ sudo systemctl start cockpit

Run the following to verify the status of cockpit service,

$ sudo systemctl status cockpit


Features of Cockpit:

Cockpit allows you to perform:

1. Service Management – Start, stop, restart, reload, disable, enable, mask e.t.c

2. User Account Management – Add users, delete, Lock, assign Administrator role, set password, force password change, Add Public SSH keys e.t.c.

3. Firewall Management

4. Cockpit Container management

5. SELinux Policy management

6. Journal v2

7. iSCSI Initiator configurations

8. SOS-reporting

9. NFS Client setup

10. Configure OpenConnect VPN Server

11. Privileged Actions – Shutdown, Restart system

12. Join Machine to Domain

13. Hardware Device Management

14. System Updates for dnf, yum, apt hosts

15. Manage the Kubernetes Node

Install XAMPP on CentOS 8 - Step by Step process to do this ?

This article covers how to install XAMPP on your CentOS system. XAMPP is an easy to install and use Apache distribution packaged with MariaDB, PHP, and Perl.

XAMPP was first developed by a project team called Apache Friends. As an open-source Apache distribution of a PHP development environment, it consists of cross-platform software (X): Apache (A), MariaDB (M), PHP (P) and Perl (P). 


To install XAMPP on CentOS 8 Linux system:

1. Update system

Ensure your CentOS system is updated.

$ sudo dnf -y update
$ sudo dnf -y install libnsl

2. Download XAMPP on CentOS 8

Install wget on CentOS 8:

$ sudo dnf -y install wget

Download XAMPP installer. Choose the installer matching the PHP version you want to have.

### PHP 8.0 ###

$ wget https://www.apachefriends.org/xampp-files/8.0.1/xampp-linux-x64-8.0.1-0-installer.run

### PHP 7.4 ###

$ wget https://www.apachefriends.org/xampp-files/7.4.14/xampp-linux-x64-7.4.14-0-installer.run

### PHP 7.3 ###

$ wget https://www.apachefriends.org/xampp-files/7.3.26/xampp-linux-x64-7.3.26-0-installer.run

3. The binary installer should be executable.

### PHP 8.0 ###

$ chmod a+x xampp-linux-x64-8.0.1-0-installer.run

### PHP 7.4 ###

$ chmod a+x xampp-linux-x64-7.4.14-0-installer.run

### PHP 7.3 ###

$ chmod a+x xampp-linux-x64-7.3.26-0-installer.run

4. Then run the XAMP installer:

### PHP 8.0 ###

$ sudo ./xampp-linux-x64-8.0.1-0-installer.run

### PHP 7.4 ###

$ sudo ./xampp-linux-x64-7.4.14-0-installer.run

### PHP 7.3 ###

$ sudo ./xampp-linux-x64-7.3.26-0-installer.run


How to Start and use XAMPP on CentOS 8:

XAMPP is installed to /opt/lampp/. To start XAMPP services, run:

$ sudo /opt/lampp/lampp start

To verify installation of XAMPP on CentOS 8 visit the Apache web page:

http://localhost


Stopping and Uninstalling XAMPP on CentOS 8:

To stop XAMPP services run:

$ sudo /opt/lampp/lampp stop

To uninstall XAMPP on CentOS 8, run:

$ cd /opt/lampp
$ sudo ./uninstall
$ sudo rm-rf /opt/lampp

Install Memcached on Ubuntu 20.04 - Step by step process ?

This article covers how you can install Memcached on Ubuntu 20.04. Memcached has proved to be a very reliable caching system since its inception in 2003 and continues to be a favorite among developers in speeding up web applications. 

Memcached is a high-performance, distributed memory object caching server. It is free and open source software intended for use in speeding up dynamic web applications by mitigating database load.


To install and configure memcached on Ubuntu:

1. Update your Ubuntu server:

$ sudo apt update
$ sudo apt upgrade

2. Install memcached server on Ubuntu:

Run apt command as follows:

$ sudo apt install memcached

3. Configure memcached server:

Edit config file named /etc/memcached.conf using a text editor such as nano command or vim command:

$ sudo nano /etc/memcached.conf

OR

$ sudo vi /etc/memcached.conf


How to restart, stop, reload memcached server on Ubuntu:

To Stop service - $ sudo systemctl stop memcached

To start Service - $ sudo systemctl start memcached

To restart Service - $ sudo systemctl restart memcached

To check the status - $ sudo systemctl status memcached

Install and Use Firewalld in CentOS / RHEL - Step by step process to implement it ?

This article covers method to Install and Use Firewalld in CentOS in order to increase the security of your Linux system. Note that the host-based firewall like firewalld is recommended by compliances like PCI DSS. 

FirewallD is a complete firewall solution that manages the system's iptables rules and provides a D-Bus interface for operating on them. Starting with CentOS 7, FirewallD replaces iptables as the default firewall management tool.

Firewalld services are predefined rules that apply within a zone and define the necessary settings to allow incoming traffic for a specific service.


How to install Firewalld on CentOS?

Firewalld is installed by default on CentOS 7, but if it is not installed on your system, you can install the package by running the command:

$ sudo yum install firewalld

Firewalld service is disabled by default. You can check the firewall status with:

$ sudo firewall-cmd --state

If you just installed or never activated before, the command will print not running. Otherwise, you will see running.

To start the FirewallD service and enable it on boot type:

$ sudo systemctl start firewalld
$ sudo systemctl enable firewalld


To open HTTP and HTTPS ports add permanent service rules to the dmz zone:

$ sudo firewall-cmd --permanent --zone=dmz --add-service=http
$ sudo firewall-cmd --permanent --zone=dmz --add-service=https

Make the changes effective immediately by reloading the firewall:

$ sudo firewall-cmd --reload

Zones provided by FirewallD:

1. drop: All incoming connections are dropped without any notification. Only outgoing connections are allowed.

2. block: All incoming connections are rejected with an icmp-host-prohibited message for IPv4 and icmp6-adm-prohibited for IPv6n. Only outgoing connections are allowed.

3. public: For use in untrusted public areas. You do not trust other computers on the network, but you can allow selected incoming connections.

4. external: For use on external networks with NAT masquerading enabled when your system acts as a gateway or router. Only selected incoming connections are allowed.

5. internal: For use on internal networks when your system acts as a gateway or router. Other systems on the network are generally trusted. Only selected incoming connections are allowed.

6. dmz: Used for computers located in your demilitarized zone that have limited access to the rest of your network. Only selected incoming connections are allowed.

7. work: Used for work machines. Other computers on the network are generally trusted. Only selected incoming connections are allowed.

8. home: Used for home machines. Other computers on the network are generally trusted. Only selected incoming connections are allowed.

9. trusted: All network connections are accepted. Trust all of the computers in the network.

Install Sublime Text Editor on CentOS 8 - Step by Step process to do it ?

This article covers how to install sublime text editor on the CentOS 8 system through the terminal. Sublime text editor is quite similar to vim editor. Sublime text has a built-in Python API available in Windows, Linux, and Mac OS.


To install Sublime Text on Ubuntu:

1. Install the GPG key:

$ wget -qO - https://download.sublimetext.com/sublimehq-pub.gpg | sudo apt-key add -

2. Ensure apt is set up to work with https sources:

$ sudo apt-get install apt-transport-https

3. Select the channel to use:

i. Stable

$ echo "deb https://download.sublimetext.com/ apt/stable/" | sudo tee /etc/apt/sources.list.d/sublime-text.list

ii. Dev

$ echo "deb https://download.sublimetext.com/ apt/dev/" | sudo tee /etc/apt/sources.list.d/sublime-text.list

4. Update apt sources and install Sublime Text:

$ sudo apt-get update
$ sudo apt-get install sublime-text


To fix yum-config-manager command not found:

You need to Install yum-utils by running the command below:

$ yum install yum-utils

Setup Teampass Passwords Manager on Ubuntu 20.04 - Do it Now ?

This article covers perform the installation of TeamPass using the LAMP stack on Ubuntu. Now you can easily manage your credentials within your Organization to save credentials and manage access to every individual. 

TeamPass is a Collaborative Passwords Manager used for managing passwords and sharing them among team members.


To Download Teampass on Ubuntu:

1. Start by cloning the Teampass repository to your web server root directory as shown below;

$ git clone https://github.com/nilsteampassnet/TeamPass.git /var/www/html/teampass

2. Set the ownership of the teampass web directory to web server user (www-data)

$ chown -R www-data.www-data /var/www/html/teampass/

3. Next, edit the /etc/php/7.2/apache2/php.ini configuration file and increase the script execution time from 30 to 60 secs.

vim /etc/php/7.2/apache2/php.ini
...
;max_execution_time = 30
max_execution_time = 60
...

4. Restart Apache web server

$ systemctl restart apache2


To Finalize TeamPass installation on Ubuntu:

Final installation of Teampass can be done from the browser. 

Hence, navigate to the browser and enter the Teampass server URL, 

http://Server_IP/teampass

This will redirect you to Teampass welcome page

Install TeamViewer on CentOS 8 - Step by Step process to get it done ?

This article covers how to install TeamViewer on the CentOS system. Additionally, you will learn how to install, launch, and update TeamViewer on CentOS.

We have also covered how to uninstall TeamViewer in case you no longer need it on your system. 

For some more help regarding TeamViewer, run teamviewer help in Terminal.

TeamViewer is a Robust cross-platform solution that provides secure remote access, remote control, and remote support solution across devices. 

The data traffic between devices are encrypted which makes the TeamViewer very secure. 

This software is available for “Linux, Windows, Mac, Chrome OS” and even for mobile devices like "iOS, Android, and so on".


To Install TeamViewer on CentOS 8:

1. Enable EPEL Repo on CentOS 8

You can install EPEL repo using the below command. This command will enable the repo if it is not already installed:

$ sudo yum install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm -y

2. Now you can proceed further to install TeamViewer on CentOS 8:

$ sudo yum install teamviewer.x86_64.rpm -y

3. Once the package is installed you can start using team viewer:

$ teamviewer

Install Skype on CentOS 8 - Step by Step process to implement it ?

This article covers how to install skype on the CentOS 8 system. One is using the RPM skype repository and another one is through the snap tool. 

Running Skype on CentOS/Fedora allows you to make Skype calls, group video calls, instant messaging, phone number calls, and screen sharing.


To Install Skype on CentOS:

1. Execute the command;

$ sudo yum localinstall skypeforlinux-64.rpm

2. Press y when prompted to confirm installation.


To Launch Skype on CentOS:

After successful installation, search Skype on your Desktop Environment search bar.

Install Nginx on Ubuntu 20.04 - Step by Step process to implement it ?

This article covers how to install Nginx on the Ubuntu system. Also, you will learn how to configure the firewall and manage Nginx services. 

Finally, you will see how to uninstall Nginx in case you no longer need it in your system.

Nginx is a free, open-source Linux application for web servers. It works as a reverse proxy server by directing web traffic to specific servers.

Also, Nginx is used for security and load-balancing, but can also function independently as a web server.


To Install Nginx From Ubuntu Repositories:

1. Update Software Repositories

It is important to refresh the repository lists before installing new software. This helps make sure that the latest updates and patches are installed.

Open a terminal window and enter the following:

$ sudo apt-get update

2. Nginx is included in the Ubuntu 20.04 default repositories. Install it by entering the following command:

$ sudo apt-get install nginx


How to manage Nginx on Ubuntu ?

The behavior of Nginx can be adjusted. Use this to start or stop Nginx, or to enable or disable Nginx at boot.

Start by checking the status of the Nginx service:

$ sudo systemctl status nginx

If the status displays active (running), Nginx has already been started. 

Press CTRL+z to exit the status display.

If Nginx is not running, use the following command to launch the Nginx service:

$ sudo systemctl start nginx

To set Nginx to load when the system starts, enter the following:

$ sudo systemctl enable nginx

To stop the Nginx service, enter the following:

$ sudo systemctl stop nginx

To prevent Nginx from loading when the system boots:

$ sudo systemctl disable nginx

To reload the Nginx service (used to apply configuration changes):

$ sudo systemctl reload nginx

For a hard restart of Nginx:

$ sudo systemctl restart nginx

To Test the Configuration

$ sudo nginx –t

The system should report that the configuration file syntax is OK, and that the configuration file test is successful.

Install Apache Web Server on CentOS 8 - Step by Step process to do it ?

This article covers how to install Apache web server on CentOS 8 distribution. With Apache we server, you can host web pages over the network. Apache is available within CentOS's default software repositories, which means you can install it with the dnf package manager.


To install Apache on CentOS:

1. Execute the command below to install the Apache package:

$ sudo dnf install httpd

After confirming the installation, dnf will install Apache and all required dependencies.

2. If you also plan to configure Apache to serve content over HTTPS, you will also want to open up port 443 by enabling the https service:

$ sudo firewall-cmd --permanent --add-service=https

3. Next, reload the firewall to put these new rules into effect:

$ sudo firewall-cmd --reload

After the firewall reloads, you are ready to start the service and check the web server.


To check your Apache Web Server:

1. Apache does not automatically start on CentOS once the installation completes, so you will need to start the Apache process manually:

$ sudo systemctl start httpd

2. Verify that the service is running with the following command:

$ sudo systemctl status httpd

You will receive an active status when the service is running.


To manage the Apache Process on CentOS:

Now that the service is installed and running, you can now use different systemctl commands to manage the service.

1. To stop your web server, type:

$ sudo systemctl stop httpd

2. To start the web server when it is stopped, type:

$ sudo systemctl start httpd

3. To stop and then start the service again, type:

$ sudo systemctl restart httpd

4. If you are simply making configuration changes, Apache can often reload without dropping connections. To do this, use this command:

$ sudo systemctl reload httpd

5. By default, Apache is configured to start automatically when the server boots. If this is not what you want, disable this behavior by typing:

$ sudo systemctl disable httpd

6. To re-enable the service to start up at boot, type:

$ sudo systemctl enable httpd

Apache will now start automatically when the server boots again.

Assign Multiple IP Addresses to Single NIC in Linux Mint 20 - How to Do it ?

This article covers how to assign multiple IP addresses to a single interface in Mint OS. By following our guide carefully, you can either assign the IP address temporarily or permanently to your network interface.

NIC stands for network interface controller or network interface (controller) card. WNIC is wireless network interface controller or wireless network interface (controller) card. IP Addresses belong to network interfaces, not to the computer itself.


To Restart network service using command:

# systemctl restart network

To Verify the new IP address using command:

# ip addr


How configure multiple IP address in CentOS ?

Now, in order to add additional IP addresses you'll need to edit the configuration file (from hereon called “config file”) for this specific interface. On CentOS 7, the interface config files are located in /etc/sysconfig/network-scripts/ and they are all prefixed with ifcfg-.


How remove secondary IP address Linux?

To add or remove additional IP adresses and keep the configuration persistent, we need to Edit the corresponding /etc/sysconfig/network-scripts/ifcfg-eth[x] configuration file and add/remove as many additional IPADDR[n] and PREFIX[n] entries as additional IP addresses are required.


To configure a static IP address on CentOS  / RHEL :

1. Create a file named /etc/sysconfig/network-scripts/ifcfg-eth0 as follows:

DEVICE=eth0.

BOOTPROTO=none.

ONBOOT=yes.

PREFIX=24.

IPADDR=your_ip_address

2. Restart network service: systemctl restart network.


How do I login as a different user in Linux?

To change to a different user and create a session as if the other user had logged in from a command prompt, type "su -" followed by a space and the target user's username. Type the target user's password when prompted.


What is Nmcli in Linux?

nmcli is a command-line tool which is used for controlling NetworkManager. nmcli commnad can also be used to display network device status, create, edit, activate/deactivate, and delete network connections. Typical Uses: Scripts: Instead of manually managing the network connections it utilize NetworkMaager via nmcli.


Difference between the output of ifconfig and ipconfig:

Functionality: The ipconfig command displays all the currently connected network interfaces whether they are active or not. 

On the other hand, the ifconfig command displays only the enabled network interfaces that are connected to the system.

Install Zimbra Collaboration Suite (ZCS) on CentOS 8 - Step by step process to do it ?

This article covers how to install Zimbra mail server on CentOS & RHEL systems. Zimbra offers two editions, the commercially supported edition called 'Network Edition' & a free/open-source version called 'Open Source Edition'. 

Zimbra Collaboration Suite (ZCS) is a collaborative software suite that includes a mail & chat server with a web client.


Main components of Zimbra Mail and Collaboration Server are:

1. Zimbra Core: These are basic libraries, utilities, monitoring tools, and basic configuration files.

2. Zimbra LDAP: This has the OpenLDAP LDAP directory server that provides authentication and configs store for users and other zimbra components.

3. Zimbra MTA (mail routing server): Has Postfix mail transfer agent (MTA) that receives email via SMTP and routes each message to the appropriate Zimbra mailbox server using Local Mail Transfer Protocol (LMTP). It also includes the anti-virus and anti-spam components.

4. Zimbra Store (Zimbra server): The mailbox server includes Data store, Message store and Index store for the mailboxes on the server. When a mail arrives, the Zimbra server schedules a thread to have the message indexed in the index store.

5. Zimbra-SNMP: This is an optional component for for monitoring and it runs on every server (Zimbra server, Zimbra LDAP, Zimbra MTA). Swatch is used to watch the syslog output to generate SNMP traps.

6. Zimbra Logger: This is an optional component for the mailbox server. It installs tools for syslog aggregation, reporting, and message tracing. This is required for the message trace feature.


To Edit your hosts file on Ubuntu:

1. $ nano –w /etc/hosts

You should have this line

Ip_address server.domain.com server

Update it as per your server information.

2. Press ctrl key + o to save

3. Press ctrl key + x to exit

4. Restart your server to take effect all the changes

$ reboot


To install Zimbra on Ubuntu server:

1. Install Zimbra prerequisites

$ apt-get update 

$ apt-get install libgmp10 libperl5.18 libaio1 pax sysstat sqlite3

2. Download Zimbra Email Server

$ wget https://files.zimbra.com/downloads/8.6.0_GA/zcs8.6.0_GA_1153.UBUNTU14_64.20141215151116.tgz

3. Unpack the file

tar xzvf zcs-8.6.0_GA_1153.UBUNTU14_64.20141215151116.tgz

4. Go to Zimbra forder

cd zcs-8.6.0_GA_1153.UBUNTU14_64.20141215151116

5. Begin installation

./install.sh

NOTE : While running the install.sh command you will be prompted with the following questions.

Do you agree with the terms of the software license agreements? [N] Y

Install zimbra-ldap [Y] Enter

Install zimbra-logger [Y] Enter

Install zimbra-mta [Y] Enter

Install zimbra-dnscache [Y] N Enter

Install zimbra-snmp [Y] Enter

Install zimbra-store [Y] Enter

Install zimbra-apache [Y] Enter

Install zimbra-spell [Y] Enter

Install zimbra-memcached [Y] Enter

Install zimbra-proxy [Y] Enter

The System will be modified. Continue? [N] Y Enter

NOTE: Do not install dnscache because we already installed bind9.

Sometimes it takes for a while to install some packages.

You will receive this error:

DNS ERROR resolving server.domain.com server

Change hostname [Yes] Enter

Please enter the logical hostname for this host [server.domain.com] domain.com

Ports conflicts detected! – Press Enter /Return key to continue Enter

Setup a password for admin account.

Change Date, Time, and Time Zone in CentOS 8 - How to do it ?

This article covers how you can easily adjust the time, date, and time zone of your system in CentOS 8.

To change the time zone in Linux systems use the sudo timedatectl set-timezone command followed by the long name of the time zone you want to set.


How to Synchronize Time on Installed Linux Operating Systems ?

1. On the Linux machine, log in as root.

2. Run the ntpdate -u <ntpserver> command to update the machine clock. For example, ntpdate -u ntp-time.

3. Open the /etc/ntp. conf file and add the NTP servers used in your environment.

4. Run the service ntpd start command to start the NTP service and implement you configuration changes.


Importance of man command in Linux:

man command in Linux is used to display the user manual of any command that we can run on the terminal. 

It provides a detailed view of the command which includes NAME, SYNOPSIS, DESCRIPTION, OPTIONS, EXIT STATUS, RETURN VALUES, ERRORS, FILES, VERSIONS, EXAMPLES, AUTHORS.

Install Slack on CentOS 8 - Step by Step process to perform it ?

This article covers how you can easily install slack platform on your CentOS 8 Linux system through the command line. 

Using a slack application, team members of an organization can unify all conversations from different sources.


Slack is one of the most popular collaboration platforms in the world that brings all your communication together. 

Conversations in Slack are organized in channels. 

You can create channels for your teams, projects, topics, or any other purpose. 

You can search through everything that's been posted in channels or your messages. 

Slack also allows you to talk with your teammates over audio or video calls and share documents, images, videos, and other files.


To Install Slack on CentOS:

1. Update system

sudo yum -y update

2. Download and Install Slack on CentOS

sudo yum -y install wget

wget https://downloads.slack-edge.com/linux_releases/slack-3.4.0-0.1.fc21.x86_64.rpm

sudo  yum -y install https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm

sudo yum localinstall slack-3.4.0-0.1.fc21.x86_64.rpm

3. Start and Use Slack

Now that Slack is installed on your CentOS / RHEL 8 desktop, you can launch it through the command line,

$ slack

Install Opera Browser on CentOS 8 - Step by step process to perform it ?

This article covers how to install the Opera browser using different ways on CentOS 8. We have also shown how you can install packages by using the wget command. Opera browser is amazing on your CentOS 8 system.


To install Opera browser on CentOS:

1. Add Opera YUM repository

Run the following commands to manually add the Opera RPM repository to your RHEL / CentOS 8 system.

$ sudo tee /etc/yum.repos.d/opera.repo <<RPMREPO

[opera]

name=Opera packages

type=rpm-md

baseurl=https://rpm.opera.com/rpm

gpgcheck=1

gpgkey=https://rpm.opera.com/rpmrepo.key

enabled=1

RPMREPO

2. Install Opera Browser on RHEL 8 / CentOS 8

Use yum package manager command to install Opera Browser on RHEL 8 / CentOS 8.

$ sudo yum -y install opera-stable

3. Wait for the installation to complete then launch the browser from the CLI:

$ opera 

Configure NFS Server and Client on Linux Mint 20 - Step by Step process to do it ?

This article covers how to setup the NFS server and client on Mint. You will learn how to install the NFS server and client, configure and share NFS export directories, and mount/unmount the NFS shares on the client.

Network File System (NFS), is a distributed file system that allows various remote systems to access a file share. We all know that files should be stored on a central server for security and ease of backup. NFS provides us with a file sharing service that is easily managed and controls client access to resources.


To Install the NFS Client on the Client Systems:

1. Install the NFS-Common Package. As is the norm, begin by updating the system packages and repositories before anything else.

2. Create a NFS Mount Point on Client.

3. Mount NFS Share on Client System.

4. Testing the NFS Share on Client System.


A Network File System (NFS) allows remote hosts to mount file systems over a network and interact with those file systems as though they are mounted locally. This enables system administrators to consolidate resources onto centralized servers on the network.


Benefits of setting up an NFS server:

1. Enables multiple computers to use the same files, so everyone on the network can access the same data.

2. Reduces storage costs by having computers share applications instead of needing local disk space for each user application.

Install Wine on CentOS 8 - Step by Step process to do it ?

This article covers how to install Wine on CentOS 8. With the use of this package, you can easily use the native Windows applications on CentOS 8. However, you can also remove this package from your CentOS 8 system to conserve the memory whenever you want.


How to Install Wine 4 on CentOS 8:

Install EPEL Repos on CentOS 8

Wine is not included in the default CentOS 8 repositories but however available on EPEL repos. Therefore, run the command below to install EPEL repos:

$ dnf install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm


To run Wine on CentOS 8:

Wine command takes the following syntax.

$ wine program [arguments]

To obtain help on Wine usage;

$ wine --help

Consult man pages for Wine for more insight.

$ man wine

Before you can use Wine to run Windows applications, reboot your system to setup the Wine environment.

$ systemctl reboot

5 Key Google Chrome Extensions

This article covers the key Google Chrome extensions which will definitely enhance your browsing experience and will make Google Chrome even more helpful and useful for you. Google Chrome extensions are programs that can be installed into Chrome in order to change the browser's functionality.

Adding to do lists or notes to Chrome. Password management. Making it easier to copy text from a site. Protect your privacy and making web browsing more secure.

Some extensions can be ethically dubious or even malicious, but Chrome features new restrictions on extension developers that should help mitigate that problem.

Install and Run Python on CentOS 8 - How to do it ?

This article covers how to install python2 and python3 on CentOS 8. By default, python2 and python3 are not installed on CentOS 8. To install both, you need to install all python packages separately according to python versions. Also, you can run python2 and python3 environments on your system. 

The 'alternatives --auto python' command is used to set any python version as the default. 


To run Python in Linux:

A widely used way to run Python code is through an interactive session. 

To start a Python interactive session, just open a command-line or terminal and then type in python, or python3 depending on your Python installation, and then hit Enter .


Python comes preinstalled on most Linux distributions, and is available as a package on all others. 

However there are certain features you might want to use that are not available on your distro's package. 

You can easily compile the latest version of Python from source.


Installing Python 3 on Linux:

1. To see which version of Python 3 you have installed, open a command prompt and run

$ python3 --version

2. If you are using Ubuntu 16.10 or newer, then you can easily install Python 3.6 with the following commands:

$ sudo apt-get update

$ sudo apt-get install python3.6

3. If you're using another version of Ubuntu (e.g. the latest LTS release) or you want to use a more current Python, we recommend using the deadsnakes PPA to install Python 3.8:

$ sudo apt-get install software-properties-common

$ sudo add-apt-repository ppa:deadsnakes/ppa

$ sudo apt-get update

$ sudo apt-get install python3.8

4. If you are using other Linux distribution, chances are you already have Python 3 pre-installed as well. If not, use your distribution's package manager. For example on Fedora, you would use dnf:

$ sudo dnf install python3


To see if pip is installed, open a command prompt and run:

$ command -v pip

Install Chrony on Linux Mint - Easy steps to do it ?

This article covers how to #install Chrony on Linux Mint 20. Once it will be installed on your system, its daemon will silently work in the background to synchronize your system's clock with the #NTP server. 

However, if you do not want Chrony to perform this job any longer, then you can simply uninstall it as well.

Chrony is a flexible implementation of the Network Time Protocol (NTP). 

It is used to synchronize the system clock from different NTP servers, reference clocks or via manual input.


Chrony comes with two programs:

1. chronyc – command line interface for chrony

2. chronyd – daemon that can be started at boot time


How to Install #Chrony in #Linux :

On some systems, chrony may be installed by default. Still if the package is missing, you can easily install it. 


You can install chrony Using your default package manager tool on your respective Linux distributions using following command:

# yum -y install chrony    [On CentOS/RHEL]

# apt install chrony       [On Debian/Ubuntu]

# dnf -y install chrony    [On Fedora 22+]


To check the status of chronyd use the following command:

# systemctl status chronyd      [On SystemD]

# /etc/init.d/chronyd status    [On Init]


If you want to enable chrony daemon upon boot, you can use the following command:

# systemctl enable chronyd       [On SystemD]

# chkconfig --add chronyd        [On Init]


How to Check Chrony Synchronization in Linux ?

To check if chrony is actually synchronized, we will use it's command line program chronyc, which has the tracking option which will provide relevant information:

# chronyc tracking


To check information about chrony’s sources, you can issue the following command:

# chronyc sources

Install and Use TermRecord on CentOS 8 - Do it now

This article Covers how to install the TermRecord application on CentOS 8. The TermRecord application allows you to better enjoy the recorded #Terminal content. 

TermRecord is a simple, open source, terminal session recorder with easy-to-share self-contained HTML output.

#TermRecord Stores these files as your own notes, email them to collaborators, use them as instructional examples, or whatever you wish.

TermRecord consumes output from the script command with timing information and can create a self-contained HTML file which replays the recorded session without needing to load anything from the web. 

These term sessions can be emailed and viewed on practically any device (including iPads etc.). 

The end user only needs a modern browser.


Features of TermRecord includes:

1. User friendly.

2. Detects the terminal size.

3. Nest sessions.

4. Cross-platform HTML-based output.

5. Stores the output as either JSON, embeddable JavaScript, or a static HTML file.

6. Written in Python.


To install on TermRecord #CentOS:

1. First of all, connect to your server via SSH and make sure that all of your system software is up to date. 

Run the following command to update the package list and upgrade all of your system software to the latest version available:

$ sudo yum update -y

2. Install Pip. 

Add the EPEL Repository:

$sudo yum install epel-release

Install pip:

$ sudo yum install python-pip

Once the installation has completed, you can verify that it was successful by using the following command:

$pip -V

3. Install TermRecord

Install TermRecord using the Python package manager (pip):

$sudo pip install TermRecord


How to use TermRecord on CentOS system ?

Taking a video of the terminal with TermRecord is rather simple, just run the following command (be attentive to capital letters):

TermRecord -o record.html

Note: We specify the output file in which the video will be recorded using the -o option. the .html format is the default format.

For more complex operations check out TermRecord --help

Assign Multiple IP Addresses to Single NIC in Debian 10 - How to do it ?

This article covers how to assign and remove multiple IP addresses to and from a single NIC. Based on your preferences, you can either assign the multiple IP addresses temporarily or permanently.

There's no simple command that you can run to determine whether the IP address on a Linux system is assigned by DHCP or static. 

If it changes when the system restarts, it's clearly dynamically assigned, but even a dynamic address has some resistance to change. 

The best way is to look at the configuration file.


To add a static route in Linux:

1. Use the route command with the –p option to add a persistent route: # route -p add default ip-address.

2. Use the route command with the –name option to add a persistent route by specifying a name rather than destination and gateway: # route -p add destination-address gateway-address -name name.


What is ip route command in Linux?

ip route is used to manipulate entries in the kernel routing tables. 

Route types: 

1. unicast - the route entry describes real paths to the destinations covered by the route prefix. 

2. unreachable - these destinations are unreachable. 

Packets are discarded and the ICMP message host unreachable is generated.

Install PostgreSQL in CentOS 8 - Step by Step Process ?

This article will cover how to install and remove the PostgreSQL server and create a database in PostgreSQL on CentOS 8. Also you will learn how to add tables in the database by using the SQL query.

PostgreSQL is available from CentOS 8's default AppStream software repository, and there are multiple versions which you can install. 

You can choose between these versions by enabling the appropriate collection of packages and dependencies that align with the version you want to install, with each collection referred to as a module stream.


To List out the available streams for the postgresql module using the dnf command:

$ dnf module list postgresql

Methods to Install Google Chrome on CentOS 8 ?

This article covers the different methods for the installation of Google Chrome on the CentOS 8 system using the terminal commands and graphical method. 

Once the installation of chrome is complete, now you can feel free to add chrome extensions and favorite themes from the web store of Google Chrome.


To install Google Chrome 78 on a RHEL/CentOS/Fedora Linux:

1. Open the Terminal application. Grab 64bit Google Chrome installer.

2. Type the following command to download 64 bit version of Google Chrome:

wget https://dl.google.com/linux/direct/google-chrome-stable_current_x86_64.rpm

3. Install Google Chrome and its dependencies on a CentOS/RHEL, type:

sudo yum install ./google-chrome-stable_current_*.rpm

4. Start Google Chrome from the CLI:

google-chrome &


To upgrade Google Chrome from an older version:

You can simply update it by typing the following yum command:

$ sudo yum update google-chrome-stable

OR use the following dnf command to update it on a Fedora Linux:

$ sudo dnf update google-chrome-stable


To uninstall Chrome from Ubuntu:

1. Open the Terminal: It should be present on your desktop or taskbar.

2. Type sudo apt-get purge google-chrome-stable and press Enter to uninstall the Chrome browser.

3. Type sudo apt-get autoremove and press Enter to clean up the Package Manager to ensure that there are no lingering files.

Install MariaDB on CentOS 8 - Step by step process ?

This article will guide you on how to install MariaDB on your CentOS 8 system. Now you can create new databases and grant privileges to other database users. Also, you can add users and create new databases for web or desktop applications which will be written in PHP, Python, and so on.

In MariaDB replication is faster whereas in MySQL replication is slower. 

MariaDB is Open Source whereas MySQL uses some proprietary code in its Enterprise Edition. 

MariaDB doesn't support Data Masking and Dynamic column while MySQL supports it. Comparatively MariaDB is faster than MySQL.


To uninstall MariaDB and install mysql:

1. Purge mariadb sudo apt purge mariadb-* Remove all databases ('Yes' answer)

2. Purge mysql sudo apt purge mysql-*

3. Remove folders: sudo rm -r /usr/share/mysql/ sudo rm -r /etc/mysql/ sudo rm -r /lib/systemd/system/mysql.service.

4. Now you can try to install oracle mysql: sudo apt install mysql-server.

Process to configure an NTP server and client on Ubuntu 20.04 LTS ?

This article will guide you on how to configure the NTP server on the #Ubuntu machine and then sync a clock of NTP client machine. Now you can easily set up NTP server and connect multiple client machines with it for time synchronization.

The Network Time Protocol (NTP) is a networking protocol for clock synchronization between computer systems over packet-switched, variable-latency data networks.

NTP is intended to synchronize all participating computers to within a few milliseconds of Coordinated Universal Time (UTC).


How do I start #NTP on Linux?

In order to add command line options to the ntpd service (/etc/init. d/ntpd), one has to edit /etc/sysconfig/ntpd file and add the desired option to the OPTIONS variable, and restart the service via 'service ntpd restart'.


What port does NTP use?

NTP time servers work within the TCP/IP suite and rely on User Datagram Protocol (UDP) port 123. NTP servers are normally dedicated NTP devices that use a single time reference to which they can synchronize a network. 

This time reference is most often a Coordinated Universal Time (UTC) source.


To Sync NTP client with server via command line:

1. Edit the /etc/ntp.

2. Search for the lines beginning server .

3. Replace the server entries with the IP address or hostname of the NTP server or servers with which you want to synchronize.

4. Save the file.

5. Configure the NTP client service to start at run level 3 when the appliance boots.

Methods to Find Your Private IP Address in CentOS 8 ?

This article will guide you on the different methods to find the private IP address in CentOS 8.


Different ways to display IP addresses in Centos:

1. Using ifconfig command. The ifconfig command is the most commonly used command for displaying and modifying IP addresses on the system.

2. Using ip command.

3. Using the hostname command.

4. using nmcli command.

5. Using ip route show command.


To configure a static IP address on CentOS 7 / RHEL 7:

1. Create a file named /etc/sysconfig/network-scripts/ifcfg-eth0 as follows:

2. DEVICE=eth0.

3. BOOTPROTO=none.

4. ONBOOT=yes.

5. PREFIX=24.

6. IPADDR=192.168.x.xxx.

7. Restart network service: systemctl restart network.


Commands will get you the private IP address of your interfaces:

i. ifconfig -a.

ii. ip addr (ip a)

iii. hostname -I | awk '{print $1}'

iv. (Fedora) Wifi-Settings→ click the setting icon next to the Wifi name that you are connected to → Ipv4 and Ipv6 both can be seen.

v. nmcli -p device show.

Reboot CentOS 8 - Different methods to do it ?

This article will guide you on the different methods to reboot a #CentOS system which includes the keyboard shortcut, command line, and GUI based methods. 

There's nothing different in running sudo reboot in a instance versus on your own server. This action shouldn't cause any problems. 

You can shutdown/start/reboot the instance and your data will persist.

When used with no arguments, the shutdown command will power off the machine. sudo shutdown. 

The shutdown process starts after 1 minute, which is the default time interval.

It is recommended that you do a #reboot of your Server at least once per month. 

The Dedicated Hosting Servers are just computers, you would not leave your computer on for months straight without a single reboot, so the same rules apply for servers.


To reboot your Linux Server via #SSH:

1. Open Command Prompt. If you have a graphical interface, open the terminal by right-clicking the Desktop > left-clicking Open in terminal.

2. Use SSH Connection Issue reboot Command. In a terminal window, type: ssh –t user@server.com 'sudo reboot'.

Display System and Hardware Details in CentOS 8 - How to do it ?

This article will guide you on different methods to retrieve information about your #Linux system and the underlying #hardware devices. These procedures will help you check the specifications of your computer machine and you can easily know either the hardware device or computer software is compatible with your working system or not.

The Linux kernel is the main component of a Linux operating system (OS) and is the core interface between a computer's hardware and its processes.


To  find system information in #Centos:

1. To know only system name, you can use uname command without any switch will print system information or uname -s #command will print the kernel name of your system. 

2. To view your network hostname, use '-n' switch with uname command as shown. 

3. To get information about kernel-version, use '-v' switch.

Install Linux, Apache, MariaDB, PHP (LAMP) Stack on Debian 10 - Step by step process to do it ?

This guide will help you on how to #install the LAMP stack (Linux, Apache, MariaDB, and PHP ) in your #Debian system. 

LAMP stands for Linux, Apache, MySQL, and PHP. Together, they provide a proven set of software for delivering high-performance web applications.

For a web application to work smoothly, it has to include an operating system, a web server, a database, and a programming language. 

A LAMP Stack is a set of open-source software that can be used to create websites and web applications. 

LAMP is an acronym, and these stacks typically consist of the Linux operating system, the Apache HTTP Server, the MySQL relational database management system, and the PHP programming language.

To Install #LAMP stack on Ubuntu:

1. Update your system. sudo apt-get update.

2. Install Mysql. sudo apt-get install mysql-server mysql-client libmysqlclient-dev.

3. Install #Apache server.

4. Install #PHP (php7.0 latest version of PHP).

5. Install #Phpmyadmin (for #database).

Methods to log out of CentOS 8 ?

This article will guide you on different methods to log out of the #CentOS 8 #Linux system. Therefore, If you want to close the current user session then, Logging out of the system is the best choice. 

The main difference between these tools is that kill terminates processes based on Process ID number (PID), while the killall and pkill commands terminate running processes based on their names and other attributes.

To exit CentOS 7:

i. Simply use 'Ctrl-C' to kill terminal commands in linux. 

ii. Ctrl-D should be used to terminate nl correctly. 

iii. Ctrl-C is just a general way to kill #applications.

Ways to Shutdown CentOS 8

This article will guide you on different ways to shut down CentOS system. Using either of the above-discussed command line or GUI way, you can easily shutdown your #CentOS system.

To shut down the system from a terminal session, sign in or "su" to the "root" account. Then type ``/sbin/shutdown -r now''. 

It may take several moments for all processes to be terminated, and then Linux will shut down.

In #Unix and #Linux, the shutdown command can be used to turn off or reboot a computer. Only the superuser can shut the system down. 

One commonly issued form of this command is shutdown -h now , which will shut down a system immediately. 

Another one is shutdown -r now to reboot.

Different methods to uninstall programs from CentOS 8 ?

This article will guide you on methods to uninstall a #package using #Yum. You need to just type the package name with root privileges. Moreover, we have also seen how to remove a single package, multiple, and group by using the Yum package manager.

apt remove just removes the binaries of a package. 

It leaves residue configuration files. apt purge removes everything related to a package including the configuration files.

To uninstall a program in #Linux Mint terminal:

1. Uninstall software in Linux mint from the main menu.

2. Confirm that you want to #remove the package.

3. Open the Software Manager.

4. Search for a program to remove using the software manager.

5. Remove software in Linux #Mint using the software manager.

6. Open Synaptic package manager.

Methods to check memory usage in CentOS 8 ?

This article will guide you on how to check the #memory #usage on the #CentOS 8 system. Moreover, we have executed different commands such as cat, free, #vmstat, top and htop that are used to display the memory information. 

sudo apt-get clean clears out the local #repository of retrieved package files.It removes everything but the lock file from /var/cache/apt/archives/ and /var/cache/apt/archives/partial/. Another possibility to see what happens when we use the command sudo apt-get clean is to simulate the execution with the -s -option.

Using these commands, you can easily get information about your system RAM, and CPU.

Commands to check memory usage on Linux:

1. free command. The free command is the most simple and easy to use command to check memory usage on linux.

2. /proc/meminfo. The next way to check memory usage is to read the /proc/meminfo file. 3. vmstat. The vmstat command with the s option, lays out the memory usage statistics much like the proc command.

5. top command.

5. htop.

Step by step process to install and configure HAproxy on Ubuntu 20.04 LTS ?

This article will guide you on how to #install and configure #HAproxy load balancer on the #Linux system. 

You will learn the basic setup and configuration of HAproxy as a load balancer for #Apache web servers. Also, we looked at some commands for managing the HAproxy server. In the end, we tested the load balancing through the browser and the #curl command. 

HAProxy is free, open source #software that provides a high availability #load #balancer and proxy server for #TCP and HTTP-based applications that spreads requests across multiple servers.

To Deploy on Linux :

1. Download the source code of HAProxy.

2. Unzip the file into the desired location tar xvzf haproxy-1.8-dev1.

3. Compile the source code.

4. Create config file haproxy.cfg with the configuration details.

5. Start the haproxy with ./haproxy -f haproxy.

6. Access the status page on http:localhost:9999/stats.

Step by step process to Install the latest MySQL on Debian 10 ?

This article will guide you on how to #install #MySQL server on Debian 10 #Linux system. Also we looked into how to secure the installation and connect with the MySQL shell. Using the Validate password #plugin you can make a more secure database MySQL password #authentication.

MySQL is an #RDBMS tostore, retrieve, modify and administrate a database usingSQL.

The mysql #command:

1. -h followed by the server host name (server.LinuxReels.com).

2. -u followed by the account user name (use your MySQL username).

3. -p which tells mysql to prompt for a password.

4. database the name of the database (use your database name).

Step by step process to install Zimbra on Ubuntu 18.04 LTS ?

This article will guide you on how to #install Zimbra on Ubuntu. Zimbra is an open-source #mail server that offers several features. It is recommended to install it in a #machine that has enough memory, processor, and disk space available. 

To install and configure #Zimbra mail server:

1. Install System Packages.

2. Configure System #Hostname.

3. Add a Static IP Address.

4. Disable Unwanted Services.

5. Install Zimbra Collaboration Suite Open Source Edition.

6. Zimba Initial Configuration.

Steps to install the latest Squid Proxy Server on Ubuntu 20.04 LTS ?

This article will guide you on steps to #install the Squid proxy server on your #Linux machine. You will also learn how to uninstall the Squid #proxy server in the #Ubuntu #machine and manage Squid services.

Squid is a caching proxy for the Web supporting HTTP, #HTTPS, FTP, and more. It reduces bandwidth and improves response times by caching and reusing frequently-requested web pages.

It is most often used in conjunction with a traditional LAMP stack (Linux, Apache, MySQL, PHP), and can be used to filter traffic on #HTTP, FTP, and HTTPS, and increase the speed (thus lower the response time) for a web server via caching.

To clear #squid proxy cache:

1. Stop the #httpd and squid services.

2. Delete the contents of the cache as follows: # rm -Rf /var/cache/rhn/*

3. Restart the squid and httpd services.

Steps to restart network services in Linux ?

This article will guide you on how to start, stop, and restart the #network service on different Linux distribution like Ubuntu, #Debian, Linux Mint, and CentOS 8. Moreover, you can troubleshoot the network #error through the #NetworkManager tool on #CentOS 8.

Please don't stop services if you have a remote ssh connection that may create a problem.

Restarting networking on a desktop machine will cause dbus and a bunch of #service to stop and never be started again, usually leading to the whole system being unusable.

To restart a Linux service:

1. Linux provides fine-grained control over system services through #systemd, using the systemctl command.

2. To verify whether a service is active or not, run this command: sudo systemctl status apache2.

3. To stop and restart the service in Linux, use the command: sudo systemctl restart SERVICE_NAME.

Steps to create and run a Perl script in Ubuntu 20.04 LTS ?

This article will guide you on steps to #install Perl and how to create and run Perl #script using the command line on #Ubuntu 20.04. We have also discussed how to configure necessary #Perl #modules on your system.

Perl is a programming language that can be used to perform tasks that would be difficult or cumbersome on the command line. Perl is included by default with most GNU / #Linux #distributions. Usually, one invokes Perl by using a text editor to write a file and then passing it to the perl #program.

Perl has a wide range of command-line options or switches that you can use. The options are also called switches because they can turn on or turn off different behaviors. For example, the -e option lets you specify a line of code directly on the command line instead of creating a script file.

To install Perl in Linux:

1. SSH to your server.

2. Change your directory to /opt by running the below command. cd /opt.

3. Download the zipped source code available for Unix/Linux.

4. After download the zip file runs the below commands to extract and install Perl.

Step by step process to install MariaDB on Linux Mint 20 ?

This article will guide you on steps to install #MariaDB on the #Linux operating system. 

MariaDB offers more and better storage engines. NoSQL support, provided by Cassandra, allows you to run SQL and NoSQL in a single database system. MariaDB also supports TokuDB, which can handle big data for large organizations and corporate users.

As a columnar database, MariaDB ColumnStore stores table data in columns rather than rows. Data partitioning by columns is also called Vertical Partitioning.

MariaDB is a drop in place replacement for #MySQL, but you can also install it alongside MySQL. 

To install MariaDB on #Ubuntu 18.04, follow these steps:

1. Update packages index. sudo apt update.

2. Once the packages list is updated, install MariaDB by issuing the following command: sudo apt install mariadb-server.

3. The MariaDB service will start automatically.

Steps to Install Webmin on Ubuntu 20.04 LTS ?

This article will guide you on the steps to install #Webmin in your Linux system. Webmin comes with a very simple webserver called miniserv.pl that is capable of doing all that is necessary for Webmin to run. However, it is not as fast or memory efficient as a well-developed server such as #Apache.

To modify the default port, 10000 to 10101, open the /etc/webmin/miniserv. conf file and modify line 1 and 16. Now you can access the Webmin through url with new custom port.

To Install Webmin on #Ubuntu:

1. Log in to your Ubuntu #server.

2. Issue the command sudo nano /etc/apt/sources. list.

3. Hit [CTRL][x] and save the file.

4. Add the downloaded key with the command sudo apt-key add jcameron-key. asc.

5. Update apt with the command sudo apt-get update.

6. Install Webmin with the command sudo apt-get install webmin.

How to install and configure DHCP server on Linux ?

This article will guide you on steps to install and configure the #DHCP #server in the Linux system and assign dynamic and fixed #IP addresses to the clients. It takes just a few simple steps to configure the DHCP server in a #Linux machine. Once you have configured it, it will automatically assign the assigning IP addresses and related information to each machine on the network.

The main DHCP #configuration file is /etc/dhcp/dhcpd. conf. The file is used to store the network configuration information required by DHCP #clients.

To enable DHCP or change other TCP/IP settings:

1. Select Start , then select Settings > #Network & Internet.

2. Do one of the following: For a Wi-Fi network, select Wi-Fi > Manage known networks.

3. Under IP assignment, select Edit.

4. Under Edit IP settings, select Automatic (DHCP) or Manual.

5. When you're done, select Save.

Steps to Create and run a Perl script in CentOS 8 ?

This article will guide you on steps to perform Perl installation on #CentOS 8. You will also learn how to create and execute the #Perl #script on your CentOS system by using the terminal #commands.

Perl is a programming language that can be used to perform tasks that would be difficult or cumbersome on the command line.

To run a Perl script in Linux:

1. Run the "perl" command with the Perl script included in the command line.

2. Run the "perl" command with the Perl script supplied from the standard input stream.

3. Run the "perl" command with the Perl script supplied in a file.

4. Run Perl script files as commands.

Easy way to Disable SELinux on CentOS 7 / RHEL 7 / Fedora Linux ?

This article will guide you on the steps to disable SELinux running on your CentOS 7, RHEL 7 and Fedora Linux. Security-Enhanced #Linux (#SELinux) is a security architecture for Linux #systems that allows administrators to have more control over who can access the system. It was originally developed by the United States National Security Agency (#NSA) as a series of patches to the Linux #kernel using Linux #Security Modules (LSM).

How To Exit Vim Text Editor Command ?

This article will guide you on how to exit #vim text editor using various options. 1. Open a new or existing file with vim filename . 2. Type i to switch into insert mode so that you can start editing the file. 3. Enter or modify the text with your file. 4. Once you're done, press the escape key Esc to get out of insert mode and back to #command mode. 5. Type :wq to save and exit your file.

How to know Ubuntu version via command line ?

This article will guide you on how to check your Ubuntu version so that you can apply patches and update versions for security and performance reasons. The Process of Checking the #Ubuntu version in the #terminal ? i. Open the terminal using "Show Applications" or use the keyboard shortcut [Ctrl] + [Alt] + [T]. ii. Type the #command "lsb_release -a" into the command line and press enter. iii. The terminal shows the Ubuntu version you're running under "Description" and "Release".

Perform SSH Installation And Configuration in CentOS

This article will guide you on the steps to install openssh server (sshd) and clients on CentOS Linux using the yum command. The #ssh #command provides a secure encrypted connection between two hosts over an insecure #network. This connection can also be used for #terminal access, file transfers, and for tunneling other applications. Graphical X11 applications can also be run securely over SSH from a remote location.

Steps to save a file in Linux command line

This article will guide you on how to use the #cat #command to display or create a new file on #Linux. To save a file, you must first be in Command mode. Press Esc to enter Command mode, and then type :wq to write and quit the file. The other, quicker option is to use the keyboard shortcut ZZ to write and quit.

Install and Configure VNC on Ubuntu 20.04 - Steps to do it.

This article will guide you on the steps to set up a secured VNC server up and running on your Ubuntu 20.04 server. This will help you to manage your files, software, and settings with a user-friendly graphical interface, and you will be able to run graphical software like web browsers remotely.

Steps to Install and Configure Nginx on Ubuntu Linux 18.04 LTS?

This tutorial will guide you on how to get Nginx server installed and configured on an Ubuntu Linux 18.04 LTS server.

Nginx is one of the most popular web servers in the world and is responsible for hosting some of the largest and highest-traffic sites on the internet. It is more resource-friendly than Apache in most cases and can be used as a web server or reverse proxy.


Nginx Configuration Files Structure

  • All configuration files are located in the /etc/nginx/ directory.
  • Nginx main configuration file is at /etc/nginx/nginx.conf.
  • It's best practice to create a separate configuration file of each domain for better maintainability.
  • New server blocks (configuration file) of each domain should be stored in /etc/nginx/sites-availabledirectory. You need to make symlink of these configuration files at /etc/nginx/sites-enabled to take in used by Nginx.
  • Activating server blocks is done by creating a symlink (a pointer) from the configuration file sites in a /etc/nginx/sites-enabled directory to the sites-enabled directory.
  • The default server web root directory is /var/www/html
  • It's best practice to to follow standard naming convention. Nginx server block files name should as domain name and must end with .conf extension. For example, your domain name is example.com then server block file name should example.com.conf
  • Nginx log files (access.log and error.log) are located in the /var/log/nginx/ directory. It's also recommended to have a different access and error log files for each server block.

How To Run a Script In Linux?

This tutorial will guide you on how to write a simple shell script and run a script in Linux operating system with help of chmod and other commands.

How to use and run bash aliases over ssh based session

This article will guide you on how to run commands and bash shell aliases on a remote machine using the ssh command.

Commands to list installed rpm packages on Linux

This article will guide you on the different commands to list all installed rpm packages on CentOS, RHEL (Red Hat Enterprise Linux), SUSE/OpenSUSE and other rpm based distros using rpm and dnf/yum command that print a list of all installed packages on your distro.

Different apt commands which you can use in Ubuntu and Debian Servers

This article will show you the different ways to use apt commands with practical examples.

Complete guide on how to modify Hostname on Ubuntu 20.04

This article will guide you on how to change your Ubuntu server hostname without restarting the system.

How to log into your Linux Server as a root user?

This article will guide you on how to run commands as root user using nonuser, su, and sudo utilities.

A complete guide on creating a Sudo User on Ubuntu 20.04 LTS

This article will help you to add a user account with access and privileges to run system administrator’s commands on Ubuntu 20.04 LTS systems.

Different methods of showing or hiding line numbers in Linux vi / vim text editor

This article will guide you on how to show or hide line numbers in vim / vi text editors using commands.

How to set up OpenVPN Server on CentOS 8 Server ?

In this article, you will learn how to set up an OpenVPN server on CentOS 8 Linux server.

The complete steps on how to add and create a Sudo User on CentOS Linux 8 sudoers

This article will guide you on how to add a new and existing user account to sudo in CentOS 8 by appending them to wheel group so that they can run admin commands.

How to install 389 Directory Server to serve as LDAP Server for your CentOS 8 / RHEL 8 Machine?

This article will take you through the steps on how to install 389 Directory Server LDAP Server on CentOS/RHEL 8.

How to configure DNS Server on CentOS 8?

Here, you will learn how to install and configure a DNS Server on CentOS 8 machine.

A complete guide on how to set up Static IP address on CentOS 8

This article will guide you on how to configure a Static IP address on CentOS 8.

How to install and configure CentOS 8 on VirtualBox

This article will guide you through the processes of Installing VirtualBox, CentOS 8 as a Virtual Machine (VM) on VirtualBox.

Method of installing MariaDB on CentOS 7

MariaDB is a very popular Database management system which is open source. It is well know as being stable and in this context , we will analyze how to get it running on your CentOS 7 Linux machine.

Setting up Let's Encrypt SSL for domains hosted on an Apache web server based on CentOS 7

Let's Encrypt has gained popularity because they offer free SSL for millions of websites all over the world. They are a non-profit certificate authority run by Internet Security Research Group (ISRG) that provides X. 509 certificates for Transport Layer Security (TLS) encryption free of charge. The certificate is usually valid for 90 days after which is expires pending when it is renewed.

Easy way to free disk space on CentOS 7

The most effective method of clearing up disk space via the inbuilt resources in CentOS. This Tutorial will show you how to free up space in your CentOS machine Safely and effectively without loosing vital files.

Installing Netdata and secure using Nginx basic http authentication

Netdata is very essential utility application which provides a real-time monitoring service for Linux systems and applications by displaying interactive charts which can be viewed via a web browser.