1、

环境信息：                       [root@joinApp2 ~]# uname -r3.10.0-123.9.3.el7.x86_64[root@joinApp2 ~]# cat /etc/redhat-releaseCentOS Linux release 7.2.1511 (Core）症状：[root@joinApp2 ~]# systemctl  start  docker.serviceJob for docker.service failed because the control process exited with error code. See "systemctl status docker.service" and "journalctl -xe" for details.[root@joinApp2 ~]# [root@joinApp2 ~]# [root@joinApp2 ~]# [root@joinApp2 ~]# systemctl status docker.service● docker.service - Docker Application Container Engine   Loaded: loaded (/usr/lib/systemd/system/docker.service; enabled; vendor preset: disabled)   Active: failed (Result: start-limit) since Thu 2016-02-25 17:26:11 CST; 16s ago     Docs:                        Process: 16384 ExecStart=/usr/bin/docker daemon $OPTIONS $DOCKER_STORAGE_OPTIONS $DOCKER_NETWORK_OPTIONS $ADD_REGISTRY $BLOCK_REGISTRY $INSECURE_REGISTRY (code=exited, status=1/FAILURE) Main PID: 16384 (code=exited, status=1/FAILURE)Feb 25 17:26:10 joinApp2 systemd[1]: Failed to start Docker Application Container Engine.Feb 25 17:26:10 joinApp2 systemd[1]: Unit docker.service entered failed state.Feb 25 17:26:10 joinApp2 systemd[1]: docker.service failed.Feb 25 17:26:11 joinApp2 systemd[1]: docker.service holdoff time over, scheduling restart.Feb 25 17:26:11 joinApp2 systemd[1]: start request repeated too quickly for docker.serviceFeb 25 17:26:11 joinApp2 systemd[1]: Failed to start Docker Application Container Engine.Feb 25 17:26:11 joinApp2 systemd[1]: Unit docker.service entered failed state.Feb 25 17:26:11 joinApp2 systemd[1]: docker.service failed.

解决办法：

（1）、

查看文件系统 /etc/docker/daemon.json 有没有这个文件，没有测创建它包括二级目录 docker

在daemon.json文件中输入以下内容:

{                                             "storage-driver"                      :                                             "devicemapper"                                             }

如果daemon.json                                            文件包含格式不正确的JSON，                      Docker将无法启动                      。

（2）、执行了一下 curl -sSL https://get.daocloud.io/daotools/set_mirror.sh | sh -s http://*******.m.daocloud.io 语句，然后 在这个文件中的/etc/docker/daemon.json 格式就变了{"registry-mirrors": ["http://****.m.daocloud.io"]，} 最后一个多了一个逗号，我猜测是这个shell语句的原因，我把逗号去掉以后，程序可以正常启动。

（3）、vi /etc/sysconfig/selinux    把selinux后面的改为disabled，重启一波机器，再重启docker就可以了

Docker 无法启动的问题：

https://my.oschina.net/u/1188877/blog/422405