steps:

1. mkdir /home/docker（你想要docker存放image的目录）

2. systemctl stop docker

3. vi /usr/lib/systemd/system/docker.service

4. 添加 -g /home/docker

[Unit]Description=Docker Application Container EngineDocumentation=https://docs.docker.comAfter=network.target docker.socketRequires=docker.socket[Service]Type=notifyExecStart=/usr/bin/docker daemon -g /home/docker -H fd://MountFlags=slaveLimitNOFILE=1048576LimitNPROC=1048576LimitCORE=infinity[Install]WantedBy=multi-user.target

5. cp -R /var/lib/docker/* /home/docker/

6. systemctl daemon-reload

7. systemctl start docker

 

done.