[updates]
name=CentOS-$releasever - updates
baseurl=http://mirrors.aliyun.com/centos/$releasever/updates/$basearch/
gpgcheck=0
[extras]
name=CentOS-$releasever - extras
baseurl=http://mirrors.aliyun.com/centos/$releasever/extras/$basearch/
gpgcheck=0
[centosplus]
name=CentOS-$releasever - centosplus
baseurl=http://mirrors.aliyun.com/centos/$releasever/centosplus/$basearch/
gpgcheck=0
[epel]
name=CentOS-$releasever - epel
baseurl=http://mirrors.aliyun.com/epel/7/x86_64/
gpgcheck=0
原文：http://blog.51cto.com/xuding/2067332