1. 下载repo文件

    下载地址：http://mirrors.163.com/.help/CentOS6-Base-163.repo

2. 备份并替换系统的repo文件

[root@localhost ~]# cd /etc/yum.repos.d/

[root@localhost ~]# mv CentOS-Base.repo CentOS-Base.repo.bak

[root@localhost ~]# mv /root/CentOS6-Base-163.repo CentOS-Base.repo

3. 执行yum源更新

[root@localhost ~]# yum clean all

[root@localhost ~]# yum makecache

[root@localhost ~]# yum update