step1: 下载安装包
$ uanme -r （查看linux版本） 分i386和x86_64
x86 地址：http://mirrors.163.com/centos/6/os/i386/Packages/
x86_64 地址：http://mirrors.163.com/centos/6/os/x86_64/Packages/
主要下载四个rpm安装包（有的版本可能依赖其他包 这时要先下载并安装依赖包）
python-iniparse-0.3.1-2.1.el6.noarch.rpm
yum-metadata-parser-1.1.2-16.el6.i686.rpm
yum-3.2.29-73.el6.centos.noarch.rpm
yum-plugin-fastestmirror-1.1.30-37.el6.noarch.rpm
版本可能有更新 注意在下载页面关键字查询
step2: 强行卸载linux自身的yum
$ rpm -qa | grep yum | xargs rpm -e —nodeps
–nodeps 强制卸载,不管依赖性
step3: 安装下载的yum包
$ rpm -ivh python-iniparse-0.3.1-2.1.el6.noarch.rpm
$ rpm -ivh yum-metadata-parser-1.1.2-16.el6.i686.rpm
$ rpm -ivh yum-3.2.29-73.el6.centos.noarch.rpm yum-plugin-fastestmirror-1.1.30-37.el6.noarch.rpm
[注] :最后2个需要一起安装，因为这2个互相依赖
[注] :本人最后2个安装的时候 需要依赖python-urlgrabber-3.9.1-11.el6.noarch.rpm包 先下载安装
$ rpm -ivh –force python-urlgrabber-3.9.1-11.el6.noarch.rpm 强制安装
step4: 下载编辑替换帮助文档
$ wget http://mirrors.163.com/.help/CentOS6-Base-163.repo
$ vim CentOS6-Base-163.repo (可以复制本文最后ps)
$ cp CentOS6-Base-163.repo /etc/yum.repo.d (移动更名)
step5: 更新yum
$ yum clean all 清除原有缓存
$ yum makecache 获取yum列表
-Metadata Cache Created (出现这个表示成功了)
感谢： http://blog.sina.com.cn/s/blog_50f908410101cto6.html
ps 更改好的帮助文档
[base]
name=CentOS-6 - Base - 163.com
baseurl=http://mirrors.163.com/centos/6/os/$basearch/
#mirrorlist=http://mirrorlist.centos.org/?release=6&arch=$basearch&repo=os
gpgcheck=1
gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6
#released updates
[updates]
name=CentOS-6 - Updates - 163.com
baseurl=http://mirrors.163.com/centos/6/updates/$basearch/
#mirrorlist=http://mirrorlist.centos.org/?release=6&arch=$basearch&repo=updates
gpgcheck=1
gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6
#additional packages that may be useful
[extras]
name=CentOS-6 - Extras - 163.com
baseurl=http://mirrors.163.com/centos/6/extras/$basearch/
#mirrorlist=http://mirrorlist.centos.org/?release=6&arch=$basearch&repo=extras
gpgcheck=1
gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6
#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-6 - Plus - 163.com
baseurl=http://mirrors.163.com/centos/6/centosplus/$basearch/
#mirrorlist=http://mirrorlist.centos.org/?release=6&arch=$basearch&repo=centosplus
gpgcheck=1
enabled=0
gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6
#contrib - packages by Centos Users
[contrib]
name=CentOS-6 - Contrib - 163.com
baseurl=http://mirrors.163.com/centos/6/contrib/$basearch/
#mirrorlist=http://mirrorlist.centos.org/?release=6&arch=$basearch&repo=contrib
gpgcheck=1
enabled=0
gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6