docker 的安装流程
sudo yum remove docker docker-client docker-client-latest docker-common docker-latest docker-latest-logrotate docker-logrotate docker-engine
sudo yum install -y yum-utils
sudo yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo
sudo yum install docker-ce docker-ce-cli containerd.io docker-compose-plugin
sudo yum install docker-ce-18.09.1 docker-ce-cli-18.09.1 containerd.io docker-compose-plugin
sudo systemctl start docker