Centos7安装Docker(2020最新亲测可用，直接复制粘贴即可)

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

yum install -y yum-utils 

yum-config-manager  --add-repo  http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

yum makecache fast

yum install docker-ce docker-ce-cli containerd.io

systemctl start docker

docker version

docker run hello-world