Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?

1、报错信息

Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?

2、原因

docker服务没有启动

3、输入以下命令启动docker服务

systemctl start docker.service

4、输入任意docker命令测试docker服务是否正常运行