1.备份yum源
mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.bak
2.下载阿里的yum
wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
或者
curl -o /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
3.清理缓存并生成新缓存
yum clean all
yum makecache
转载于:https://www.cnblogs.com/go2anywhere/p/11237483.html
相关资源：数据结构—成绩单生成器