refer:https://www.cnblogs.com/abc1069/p/17496240.html
sudo mkdir -p /etc/systemd/system/docker.service.d
编辑文件
nano /etc/systemd/system/docker.service.d/http-proxy.conf
添加内容
[Service]
Environment="HTTP_PROXY=http://proxy.example.com:80"
Environment="HTTPS_PROXY=https://proxy.example.com:443"
服务重载
systemctl daemon-reload
重启服务
service docker restart
查看是否生效
systemctl show --property=Environment docker