1.备份本地yum源
[root@bogon ~]# mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo_bak
2.获取阿里yum源配置文件
[root@bogon ~]# wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
3.更新yum缓存
[root@bogon ~]# yum makecache