安装docker

1.之前下过docker又想重装就执行以下命令

$ sudo yum remove docker 
docker-client 
docker-client-latest 
docker-common 
docker-latest 
docker-latest-logrotate 
docker-logrotate 
docker-engine

2.使用yum命令安装docker

yum install docker

3.启动docker

systemctl start docker

4.测试运行 hello-world

docker run hello-world