docker+k8s服务器启动不了
1.服务器进不了系统
1.报错：
XFS(sda5):metadata I/O error:block 0xdc61a01（"xfs_trans_read_buf_map"） error 117 numblks 1
...
Failed to mount /sysroot
解决：
1）先使用U盘安装一个centos7 LiveGNOME系统
2）启动u盘centos7系统 ，进入系统，输入xfs_repair -L /dev/sdb5 (使用u盘系统后，原先硬盘变为sdb)
2.docker服务器启动后，docker服务启动失败
报错：
Job for docker.service failed because the control process exited with error code. See "systemctl status docker.service" and "journalctl -xe" for details.
[root@ALY-HKC-PRO-001 ~]# systemctl status docker
● docker.service - Docker Application Container Engine
Loaded: loaded (/usr/lib/systemd/system/docker.service; disabled; vendor preset: disabled)
Active: failed (Result: exit-code) since Mon 2017-07-03 10:12:16 CST; 5s ago
Docs: http://docs.docker.com
Process: 16172 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 $OPTIONS $DOCKER_STORAGE_OPTIONS $DOCKER_NETWORK_OPTIONS $ADD_REGISTRY $BLOCK_REGISTRY $INSECURE_REGISTRY (code=exited, status=1/FAILURE)
Main PID: 16172 (code=exited, status=1/FAILURE)
Jul 03 10:12:15 ALY-HKC-PRO-001 systemd[1]: Starting Docker Application Container Engine...
Jul 03 10:12:15 ALY-HKC-PRO-001 dockerd-current[16172]: time="2017-07-03T10:12:15.812330534+08:00" level=info msg="libcontainerd: new containerd process, pid: 16180"
Jul 03 10:12:16 ALY-HKC-PRO-001 dockerd-current[16172]: time="2017-07-03T10:12:16.823237678+08:00" level=warning msg="devmapper: Usage of loopback devices is strongly discourage...v section."
Jul 03 10:12:16 ALY-HKC-PRO-001 dockerd-current[16172]: time="2017-07-03T10:12:16.838204058+08:00" level=error msg="[graphdriver] prior storage driver \"devicemapper\" failed: d...run failed"
Jul 03 10:12:16 ALY-HKC-PRO-001 dockerd-current[16172]: time="2017-07-03T10:12:16.838278116+08:00" level=fatal msg="Error starting daemon: error initializing graphdriver: devmap...run failed"
Jul 03 10:12:16 ALY-HKC-PRO-001 systemd[1]: docker.service: main process exited, code=exited, status=1/FAILURE
Jul 03 10:12:16 ALY-HKC-PRO-001 systemd[1]: Failed to start Docker Application Container Engine.
Jul 03 10:12:16 ALY-HKC-PRO-001 systemd[1]: Unit docker.service entered failed state.
Jul 03 10:12:16 ALY-HKC-PRO-001 systemd[1]: docker.service failed.
Hint: Some lines were ellipsized, use -l to show in full.
解决：
删除docker目录,重启docker服务
#rm -fr /data/docker
#systemctl restart docker