centos镜像源切换

 更新为阿里的参考

https://developer.aliyun.com/mirror/centos

https://developer.aliyun.com/mirror/epel

下载前备份之前的源

cd /etc/yum.repos.d/&&mkdir backup&&mv * backup

下载centos源

curl -o /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-7.repo

运行yum makecache 生成本地缓存

再试试yum install wget就可以了

下载eple源

wget -O /etc/yum.repos.d/epel.repo https://mirrors.aliyun.com/repo/epel-7.repo