1.安装Wget
 
yum -y install wget
 
2.备份本地yum源
 
mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo_bak
 
3.获取阿里yum源配置文件
 
wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
 
4.更新yum缓存
 
yum makecache
 
然后就可以了