from: http://*.com/questions/23111631/cannot-download-docker-images-behind-a-proxy
That's an old subject, but I'll give my two cents in case someone else is looking for advice.
Here is a link to the official docker doc for proxy http:https://docs.docker.com/engine/admin/systemd/#http-proxy
A quick outline:
First, create a systemd drop-in directory for the docker service:
mkdir /etc/systemd/system/docker.service.d
Now create a file called /etc/systemd/system/docker.service.d/http-proxy.conf that adds the HTTP_PROXY environment variable:
[Service]
Environment="HTTP_PROXY=http://proxy.example.com:80/"
If you have internal Docker registries that you need to contact without proxying you can specify them via the NO_PROXY environment variable:
Environment="HTTP_PROXY=http://proxy.example.com:80/"
Environment="NO_PROXY=localhost,127.0.0.0/8,docker-registry.somecorporation.com"
Flush changes:
$ sudo systemctl daemon-reload
Verify that the configuration has been loaded:
$ sudo systemctl show --property Environment docker
Environment=HTTP_PROXY=http://proxy.example.com:80/
Restart Docker:
$ sudo systemctl restart docker