(一)centos7.3安装docker,配置镜像源

先看文档：https://docs.docker.com/engine/installation/linux/docker-ce/centos/

1. sudo yum remove docker

                  docker-common 
                  docker-selinux 
                  docker-engine

2.

$ sudo yum install -y yum-utils 
  device-mapper-persistent-data 
  lvm2

3.

 sudo yum-config-manager 
    --add-repo 
    https://download.docker.com/linux/centos/docker-ce.repo

4.

 yum list docker-ce --showduplicates | sort -r

sudo yum install docker-ce