1. 备份源文件

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

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

CentOS 5

# wget -O /etc/yum.repos.d/CentOS-Base.repo img/20170809/y3duec5uleq.repo

CentOS 6

# wget -O /etc/yum.repos.d/CentOS-Base.repo img/20170809/5zetc02drr5.repo

CentOS 7

# wget -O /etc/yum.repos.d/CentOS-Base.repo img/20170809/jefx2ychhp0.repo

3. 生成缓存

# yum makecache

参考： img/20170809/k0nwkk3to4t

---