docker.service启动报错的一次排查详解

　　● docker.service - Docker Application Container Engine

　　Loaded: loaded (/usr/lib/systemd/system/docker.service; disabled; vendor preset: disabled)

　　Drop-In: /etc/systemd/system/docker.service.d

　　└─kolla.conf

　　Active: failed (Result: exit-code) since 三 2018-08-01 16:32:27 CST; 52min ago

　　Docs: https://docs.docker.com

　　Process: 3833722 ExecStart=/usr/bin/docker daemon --insecure-registry 172.16.59.153 (code=exited, status=1/FAILURE)

　　Main PID: 3833722 (code=exited, status=1/FAILURE)

　　Memory: 8.0K

　　CGroup: /system.slice/docker.service

　　8月 01 16:32:26 czwei004 systemd[1]: Starting Docker Application Container Engine...

　　8月 01 16:32:26 czwei004 docker[3833722]: time="2018-08-01T16:32:26.527063936+08:00" level=info msg="libcontainerd: new containerd process, pid: 3833733"

　　8月 01 16:32:27 czwei004 docker[3833722]: time="2018-08-01T16:32:27.532317497+08:00" level=warning msg="devmapper: Usage of loopback devices is strongly discouraged for production use. Please use `--storage-opt dm.thinpooldev` or use `man docker` to refer to dm.thinpooldev section."

　　8月 01 16:32:27 czwei004 docker[3833722]: time="2018-08-01T16:32:27.560010414+08:00" level=warning msg="devmapper: Base device already exists and has filesystem xfs on it. User specified filesystem will be ignored."

　　8月 01 16:32:27 czwei004 docker[3833722]: time="2018-08-01T16:32:27.577758251+08:00" level=fatal msg="Error starting daemon: error initializing graphdriver: "/var/lib/docker" contains several valid graphdrivers: devicemapper, overlay2; Please cleanup or explicitly choose storage driver (-s )"

　　8月 01 16:32:27 czwei004 systemd[1]: docker.service: main process exited, code=exited, status=1/FAILURE

　　8月 01 16:32:27 czwei004 systemd[1]: Failed to start Docker Application Container Engine.

　　8月 01 16:32:27 czwei004 systemd[1]: Unit docker.service entered failed state.

　　8月 01 16:32:27 czwei004 systemd[1]: docker.service failed.