通过命令行查看docker服务是否已启动的方法如下：
查看docker的运行状态systemctl status docker
输出如下：[root@izr86o15kikb3az /]# systemctl status docker
● docker.service - Docker Application Container Engine
Loaded: loaded (/usr/lib/systemd/system/docker.service; enabled; vendor preset: disabled)
Active: active (running) since Thu -10-24 16:05:01 CST; 29s ago
Docs:
Main PID: 6485 (dockerd)
Tasks: 9
Memory: 111.3M
CGroup: /system.slice/docker.service
└─6485 /usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock
Oct 24 16:05:01 izr86o15kikb3az dockerd[6485]: time="-10-24T16:05:01.127523857+08:00" level=info msg="ccResolverWrapper
