1、修改yum的fastestmirror.conf
# sed -i "s|enabled=1|enabled=0|g" /etc/yum/pluginconf.d/fastestmirror.conf
2、备份原来的yum源文件
# mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.backup
3、下载新的yum源文件
# curl -o /etc/yum.repos.d/CentOS-Base.repo https://www.xmpan.com/Centos-6-Vault-Aliyun.repo
4、刷新yum缓存
# yum clean all && yum makecache