#!/bin/bash 
## 备份 /etc/yum.repos.d/CentOS-Base.repo 
sudo cp /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.$(date "+%y%m%d%H%M%S").backup 
## 更换为阿里源 
sudo curl -o /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-7.repo 
## 安装epel 
sudo yum install -y epel-release 
## 使用阿里提供的epel源 
sudo curl -o /etc/yum.repos.d/epel-7.repo http://mirrors.aliyun.com/repo/epel-7.repo 
## 安装yum必要的一些系统工具 
sudo yum install -y yum-utils device-mapper-persistent-data lvm2 
## 添加软件源信息 
sudo yum-config-manager --add-repo https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo 
## Step 3 
sudo sed -i 's+download.docker.com+mirrors.aliyun.com/docker-ce+' /etc/yum.repos.d/docker-ce.repo 
## 清空yum缓存 
sudo yum clean all 
## 重建yum缓存 
sudo yum makecache fast