文章目录

1.下载阿里云repo文件

 wget http://mirrors.aliyun.com/repo/Centos-7.repo

2.备份并替换系统的repo文件

  mv Centos-7.repo /etc/yum.repos.d/ 
  cd /etc/yum.repos.d/ 
  mv CentOS-Base.repo CentOS-Base.repo.bak 
  mv Centos-7.repo CentOS-Base.repo

3.执行yum源更新命令

  yum clean all 
  yum makecache 
  yum update