1.删除redhat原有的yum 
rpm -aq|grep yum|xargs rpm -e --nodeps

2.下载yum安装文件

wget http://mirrors.163.com/centos/6/os/x86_64/Packages/yum-3.2.27-14.el6.centos.noarch.rpm 
wget http://mirrors.163.com/centos/6/os/x86_64/Packages/yum-metadata-parser-1.1.2-14.1.el6.x86_64.rpm 
wget http://mirrors.163.com/centos/6/os/x86_64/Packages/yum-plugin-fastestmirror-1.1.26-11.el6.noarch.rpm 
wget http://mirrors.163.com/centos/6/os/x86_64/Packages/python-iniparse-0.3.1-2.1.el6.noarch.rpm 

3.进行安装yum 

rpm -ivh python-iniparse-0.3.1-2.1.el6.noarch.rpm 
rpm -ivh yum-metadata-parser-1.1.2-14.1.el6.x86_64.rpm 
rpm -ivh yum-3.2.27-14.el6.centos.noarch.rpm um-plugin-fastestmirror-1.1.26-11.el6.noarch.rpm  
注意最后两个包必需同时安装，否则会相互依赖

我的安装到这就可以了。

参考文档：http://www.centoscn.com/CentOS/2015/0212/4696.html