yum更换阿里源

备份
mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.backup

下载新的CentOS-Base.repo 到/etc/yum.repos.d/

CentOS 5

wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-5.repo

CentOS 6

wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-6.repo

CentOS 7

wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo

运行  yum makecache    生成缓存

让yum重新缓存新的数据

yum update


sohu的源：http://mirrors.sohu.com/help/CentOS-Base-sohu.repo 

163的源：http://mirrors.163.com/.help/CentOS6-Base-163.repo 

阿里云的源：http://mirrors.aliyun.com/repo/Centos-7.repo

参考：https://www.jianshu.com/p/e63903fd09f0
参考：https://blog.csdn.net/qq_36731677/article/details/58288979