EPEL 是 Extra Packages for Enterprise Linux 的缩写（EPEL），是用于 Fedora-based Red Hat Enterprise Linux (RHEL) 的一个高质量软件源EPEL(http://fedoraproject.org/wiki/EPEL) 是由 Fedora 社区打造，为 RHEL 及衍生发行版如 CentOS、Scientific Linux 等提供高质量软件包的项目。
安装EPEL源
官方源直接安装
rpm -Uvh http://dl.fedoraproject.org/pub/epel/7/x86_64/e/epel-release-7-5.noarch.rpm
国内的往往速度会更快
#中科大镜像源 高质量源 rpm -Uvh http://mirrors.ustc.edu.cn/centos/7.0.1406/extras/x86_64/Packages/epel-release-7-5.noarch.rpm #浙大源 也非常不错 rpm -Uvh http://mirrors.zju.edu.cn/epel/7/x86_64/e/epel-release-7-5.noarch.rpm #上海交大源，更新比较快 rpm -Uvh http://ftp.sjtu.edu.cn/fedora/epel/7/x86_64/e/epel-release-7-5.noarch.rpm #还有东北的活雷锋东软的源，最近有些抽风，经常打不开 http://mirrors.neusoft.edu.cn/epel/7/x86_64/e/epel-release-7-5.noarch.rpm #sohu镜像源，更新比较慢 rpm -Uvh http://mirrors.sohu.com/fedora-epel/7/x86_64/e/epel-release-7-2.noarch.rpm
这是来自官方公布的数据（2015-01-28）
http://mirrors.fedoraproject.org/publiclist/EPEL/7/x86_64/#CN
配置EPEL源
vi /etc/yum.repos.d/epel.repo
[epel] name=Extra Packages for Enterprise Linux 7 - $basearch baseurl=http://ftp.sjtu.edu.cn/fedora/epel/7/$basearch #mirrorlist=https://mirrors.fedoraproject.org/metalink?repo=epel-7&arch=$basearch failovermethod=priority enabled=1 gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-7 [epel-debuginfo] name=Extra Packages for Enterprise Linux 7 - $basearch - Debug baseurl=http://ftp.sjtu.edu.cn/fedora/epel/7/$basearch/debug #mirrorlist=https://mirrors.fedoraproject.org/metalink?repo=epel-debug-7&arch=$basearch failovermethod=priority enabled=0 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-7 gpgcheck=1 [epel-source] name=Extra Packages for Enterprise Linux 7 - $basearch - Source baseurl=http://ftp.sjtu.edu.cn/fedora/epel/7/SRPMS #mirrorlist=https://mirrors.fedoraproject.org/metalink?repo=epel-source-7&arch=$basearch failovermethod=priority enabled=0 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-7 gpgcheck=1
vi /etc/yum.repos.d/epel-testing.repo
[epel-testing] name=Extra Packages for Enterprise Linux 7 - Testing - $basearch baseurl=http://ftp.sjtu.edu.cn/fedora/epel/testing/7/$basearch #mirrorlist=https://mirrors.fedoraproject.org/metalink?repo=testing-epel7&arch=$basearch failovermethod=priority enabled=0 gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-7 [epel-testing-debuginfo] name=Extra Packages for Enterprise Linux 7 - Testing - $basearch - Debug baseurl=http://ftp.sjtu.edu.cn/fedora/epel/testing/7/$basearch/debug #mirrorlist=https://mirrors.fedoraproject.org/metalink?repo=testing-debug-epel7&arch=$basearch failovermethod=priority enabled=0 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-7 gpgcheck=1 [epel-testing-source] name=Extra Packages for Enterprise Linux 7 - Testing - $basearch - Source baseurl=http://ftp.sjtu.edu.cn/fedora/epel/testing/7/SRPMS #mirrorlist=https://mirrors.fedoraproject.org/metalink?repo=testing-source-epel7&arch=$basearch failovermethod=priority enabled=0 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-7 gpgcheck=1
这是已经替换好上海交大源的文件，如果想使用中科大的，请用http://mirrors.ustc.edu.cn/来替换http://ftp.sjtu.edu.cn/fedora/就可。其它以此来推。
检查源是否已添加
yum repolist
运行命令生成缓存
yum clean all && yum makecache
选择速度最快的yum源
yum安装插件yum-plugin-fastestmirror
yum install yum-plugin-fastestmirror