1. 下载docker-ce的repo
curl https://download.docker.com/linux/centos/docker-ce.repo -o /etc/yum.repos.d/docker-ce.repo
2. 安装依赖(centos7 不用这一步，centos8需要)
yum install https://download.docker.com/linux/fedora/30/x86_64/stable/Packages/containerd.io-1.2.6-3.3.fc30.x86_64.rpm
3. 安装docker-ce
yum install docker-ce
4. 启动docker
systemctl start docker
卸载
1. 查询安装过的包
yum list installed | grep docker
输出：
docker-ce.x86_64 ……
docker-ce-cli.x86_64
2. 删除安装的软件包
yum -y remove docker-ce.x86_64
yum -y remove docker-ce-cli.x86_64
3. 删除镜像/容器等
rm -rf /var/lib/docker/
4. 输入docker或docker –version验证是否卸载
docker –version
输出：
-bash: /usr/bin/docker: No such file or directory