[root@localhost ~]# systemctl start docker
Job for docker.service failed because the control process exited with error code. See "syste
mctl status docker.service" and "journalctl -xe" for details.
查看错误信息：
[root@localhost ~]# docker -v
Docker version 1.13., build b2f74b2/1.13.
[root@localhost ~]# systemctl status docker.service -l
● docker.service - Docker Application Container Engine
Loaded: loaded (/usr/lib/systemd/system/docker.service; disabled; vendor preset: disabled)
Active: failed (Result: exit-code) since Wed -- :: EDT; 14min ago
Docs: http://docs.docker.com
Process: ExecStart=/usr/bin/dockerd-current --add-runtime docker-runc=/usr/libexec/docker/docker-runc-current --default-runtime=docker-runc --exec-opt native.cgroupdriver=systemd --userland-
proxy-path=/usr/libexec/docker/docker-proxy-current --init-path=/usr/libexec/docker/docker-init-current --seccomp-profile=/etc/docker/seccomp.json $OPTIONS $DOCKER_STORAGE_OPTIONS $DOCKER_NETWORK_O
PTIONS $ADD_REGISTRY $BLOCK_REGISTRY $INSECURE_REGISTRY $REGISTRIES (code=exited, status=/FAILURE)
Main PID: (code=exited, status=/FAILURE) Jun :: localhost.localdomain systemd[]: Starting Docker Application Container Engine...
Jun :: localhost.localdomain dockerd-current[]: time="2019-06-19T04:25:24.402861259-04:00" level=warning msg="could not change group /var/run/docker.sock to docker: group docker not fo
und"
Jun :: localhost.localdomain dockerd-current[]: time="2019-06-19T04:25:24.418276049-04:00" level=info msg="libcontainerd: new containerd process, pid: 5417"
Jun :: localhost.localdomain dockerd-current[]: time="2019-06-19T04:25:25.440697173-04:00" level=warning msg="overlay2: the backing xfs filesystem is formatted without d_type support,
which leads to incorrect behavior. Reformat the filesystem with ftype= to enable d_type support. Running without d_type support will no longer be supported in Docker 1.16."
Jun :: localhost.localdomain dockerd-current[]: Error starting daemon: SELinux is not supported with the overlay2 graph driver on this kernel. Either boot into a newer kernel or disabl
e selinux in docker (--selinux-enabled=false)
Jun :: localhost.localdomain systemd[]: docker.service: main process exited, code=exited, status=/FAILURE
Jun :: localhost.localdomain systemd[]: Failed to start Docker Application Container Engine.
Jun :: localhost.localdomain systemd[]: Unit docker.service entered failed state.
Jun :: localhost.localdomain systemd[]: docker.service failed.
关键信息：SELinux is not supported with the overlay2 graph driver on this kernel.
分析原因：此linux的内核中的SELinux不支持 overlay2 graph driver
重新编辑docker配置文件： vi /etc/sysconfig/docker
修改 –selinux-enabled=false
重新启动docker： [root@localhost ~]# systemctl start docker
启动成功！
