Get Docker CE for CentOS

//https://docs.docker.com/install/linux/docker-ce/centos/

To get started with Docker CE on CentOS, make sure you meet the prerequisites, then install Docker.

// meet  vt. 满足；遇见；对付      prerequisite  n.先决条件

Prerequisites

OS requirements

To install Docker CE, you need a maintained version of CentOS 7. Archived versions aren’t supported or tested.

The centos-extras repository must be enabled. This repository is enabled by default, but if you have disabled it, you need to re-enable it.

The overlay2 storage driver is recommended.

Uninstall old versions

Older versions of Docker were called docker or docker-engine. If these are installed, uninstall them, along with associated dependencies.

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

It’s OK if yum reports that none of these packages are installed.  //如果yum 报告这些包都没有安装，那也没关系