您可以使用以下命令来检查 Docker 服务是否正在运行：
sudo systemctl status docker
如果服务正在运行，则会显示类似以下内容的输出：
● docker.service - Docker Application Container Engine
Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled)
Active: active (running) since Mon 2021-10-11 12:34:56 UTC; 2min ago
Docs: https://docs.docker.com
Main PID: 12345 (dockerd)
Tasks: 8
Memory: 162.1M
CPU: 1.576s
CGroup: /system.slice/docker.service
├─12345 /usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock
└─12357 containerd --config /var/run/containerd/containerd.toml --log-level info
如果服务未运行，则会显示类似以下内容的输出：
● docker.service - Docker Application Container Engine
Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled)
Active: inactive (dead) since Mon 2021-10-11 12:34:56 UTC; 2min ago
Docs: https://docs.docker.com
Process: 12345 ExecStart=/usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock (code=exited, status=1/FAILURE)
Main PID: 12345 (code=exited, status=1/FAILURE)
如需启动或停止 Docker 服务，您可以使用以下命令：
启动 Docker 服务：
sudo systemctl start docker
停止 Docker 服务：
sudo systemctl stop docker
