服务器上被新来的小伙伴不知道弄了啥，docker没法用了，具体报错如下：
docker ps -a Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?找了找解决方法，其实就是关闭docker，再重新启动，具体如下：
service docker stop systemctl stop docker systemctl start docker # 检查发现docker又可以使用了。。。。 docker ps -a一些常用的docker命令：
Docker启动命令1: sudo systemctl start docker
Docker启动命令2: sudo service docker start
Docker重启命令1: sudo systemctl restart docker
Docker重启命令2: sudo service docker restart
docker关闭命令1: sudo systemctl stop docker
docker关闭命令2: sudo service docker stop
守护进程重启: sudo systemctl daemon-reload
设置Docker开机自启动方式1: systemctl enable docker.service
设置Docker开机自启动方式2: chkconfig docker on
关闭Docker开机启动: systemctl disable docker.service
查看是否设置开机启动列表: systemctl list-unit-files | grep enable
参考链接：
- https://blog.csdn.net/lihongdou/article/details/103307015?utm_medium=distribute.pc_relevant.none-task-blog-title-2&spm=1001.2101.3001.4242
