CentOS7更改成阿里云的源

#备份本地yum源文件
mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo_bak
#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
#更新cache
yum makecache
yum -y update 

参考

https://blog.csdn.net/zsq843850851/article/details/106661386