Sometimes Docker users are unable to download Docker images behind a proxy due to issues with the Docker proxy settings.
In this context, we shall look into method to fix this Docker error.
We had a customer who installed Docker on his Ubuntu server. Then he tried running the below command:
$ sudo docker pull busybox
As a result, he received the below error:
Pulling repository busybox
2021/03/16 09:37:07 Get https://index.docker.io/v1/repositories/busybox/images: dial tcp: lookup index.docker.io on 127.0.1.1:53: no answer from server
In order to resolve this problem, we first create a systemd drop-in directory for the Docker service by running the below command.
$ mkdir /etc/systemd/system/docker.service.d
Next, we create a file called /etc/systemd/system/docker.service.d/http-proxy.conf that adds the HTTP_PROXY environment variable:
Note: In case, if you have internal Docker registries that you need to contact without proxying you can specify them via the NO_PROXY environment variable:
After that, we flush the changes by running the below command:
$ sudo systemctl daemon-reload
Then we verify if the configuration is loaded or not. For that, we run the below command:
$ sudo systemctl show --property Environment docker
Finally, we restart the Docker by running the below command:
$ sudo systemctl restart docker
Finally, this fixed the Docker error.