Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running
Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running? 遇到这种报错，仔细看错误信息，其实描述很清楚，docker守护进程可能没有运行，启动 docker即可(systemctl start docker)。
