1、RHEL/CentOS/SL Linux 6.x 下安装 EPEL6 yum源：
32位系统选择：
rpm -ivh http://download.fedora.redhat.com/pub/epel/6/i386/epel-release-6-5.noarch.rpm
64位系统选择：
rpm -ivh http://download.fedora.redhat.com/pub/epel/6/x86_64/epel-release-6-5.noarch.rpm
2、导入key：
rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-6
3、更新
yum update