centos yum 数据源切换

1.下载数据源

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

2.备份数据源

cd /etc/yum.repos.d/
mv Centos-Base.repo Centos-Base.repo_back

3.复制新数据源

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

更新数据源

yum clean all
yum makecache
yum -y update