vim /etc/systemd/system/docker.service.d/http-proxy.conf

-------
[Service]
Environment="HTTP_PROXY=http://proxy.hostname:80/"
Environment="HTTPS_PROXY=http://proxy.hostname:80/"
Environment="NO_PROXY="localhost,127.0.0.1,::1"
------

systemctl daemon-reload
systemctl restart docker
systemctl status docker

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