更新一下yum：
yum -y update
安装containerd.io
yum install https://download.docker.com/linux/fedora/30/x86_64/stable/Packages/containerd.io-1.2.6-3.3.fc30.x86_64.rpm
安装一些其他依赖
yum install -y yum-utils device-mapper-persistent-data lvm2`
`yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo
安装docker
yum install -y docker-ce
启动docker
systemctl start docker
