#!/bin/sh#Enter the yum configuration file directorycd /etc/yum.repos.d/#Backup configuration filebase_file=CentOS-Base.repoif [ -f "base_file" ];then  mv CentOS-Base.repo CentOS-Base.repo.bakfi#download 163 configuration filewget http://mirrors.163.com/.help/CentOS6-Base-163.repo#change 163 configuration file become base_configurationdown_file=CentOS6-Base-163.repoif [ -f "down_file" ];then  mv CentOS6-Base-163.repo CentOS-Base.repoelse echo "Down 163 configuration fail ->Fail" fi#update yum infoyum update