迁移到：
/data/docker/lib
在/etc/systemd/system/docker.service.d/devicemapper.conf里面配置,没有的话创建文件
[Service]
ExecStart=
ExecStart=/usr/bin/dockerd --graph=/data/docker/lib
停机docker
systemctl stop docker
cp -R /var/lib/docker/* /data/docker/lib/
重载配置，重启docker
systemctl daemon-reload
systemctl restart docker
systemctl enable docker