RHEL是提供给企业使用的，虽然我们在网络上也能下载到它的镜像，但是我们无法使用它的服务。最近由于系统比较卡，重装了一次系统，装完之后，我用VMware Workstation Pro 12 加载了之前的RHEL 6.9-000002.vmdk文件之后居然发现不能挂载CD/DVD，这就不能愉快的玩了。在VMware的设置里折腾好久也没能搞定，光盘安装RPM包是没希望了，联想的最近学过的的YUM ，又重新燃起了希望。

Red Hat的yum在线更新是收费的，未注册则不能使用。既然无法使用RHEL的服务，那咱就给它换与它“一母同胞”的CentOS的YUM源，考虑到网速的原因，我选择了网易的源（http://mirrors.163.com/centos/6.9/os/x86_64/Packages/），接下来，开始我们的RHEL换源记。(下文所有操作以root用户执行)

1 准备

    首先，我们需要先删除旧的的yum文件，保持一个纯净的安装环境，可以大大提高我们的成功率。

     rpm -aq|grep yum|xargs rpm -e –nodeps

2下载RPM包文件

            打开http://mirrors.163.com/centos/6.9/os/x86_64/Packages/点击即可手动下载（网上有许多通过wget方式下载，大家可以参考简单的方式来实现自己 的预定目标）

    yum-3.2.29-81.el6.centos.noarch.rpm 
    yum-plugin-fastestmirror-1.1.30-40.el6.noarch.rpm
    yum-metadata-parser-1.1.2-16.el6.x86_64.rpm
    python-iniparse-0.3.1-2.1.el6.noarch.rpm

3安装YUM

      rpm -ivh python-iniparse-0.3.1-2.1.el6.noarch.rpm
      rpm -ivh yum-metadata-parser-1.1.2-16.el6.x86_64.rpm
      rpm -ivh yum-plugin-fastestmirror-1.1.30-40.el6.noarch.rpm

  执行到这步的时候出了一个坑，出现了如下提示

      yum >= 3.0 is needed by yum-plugin-fastestmirror-1.1.30-40.el6.noarch

      那就先yum-3.2.29-81.el6.centos.noarch.rpm 吧，但是，不幸的事情又发生了

    yum-plugin-fastestmirror is needed by yum-3.2.29-81.el6.centos.noarch

      它两不离不弃，却把我坑死了，回头一想，不让它检查依赖关系不就好了，果断实验一下，居然成功了。

     rpm -ivh yum-3.2.29-81.el6.centos.noarch.rpm --force --nodeps
     rpm -ivh yum-plugin-fastestmirror-1.1.30-40.el6.noarch.rpm --force --nodeps

4配置yum

          <1>进入/etc/yum.repos.d/目录

     cd /etc/yum.repos.d/

          <2>清空

      rm  -rf  *  

          <3>获取新的配置文件

      wget http://mirrors.163.com/.help/CentOS6-base-163.repo

          <4>修改配置文件

      vim CentOS6-base-163.repo

    给大家贴一份修改好的配置文件，大家可以把版本号修改一下，看看能不能正常运行，祝大家好运！

     1 # CentOS-Base.repo
     2 #
     3 # The mirror system uses the connecting IP address of the client and the
     4 # update status of each mirror to pick mirrors that are updated to and
     5 # geographically close to the client.  You should use this for CentOS updates
     6 # unless you are manually picking other mirrors.
     7 #
     8 # If the mirrorlist= does not work for you, as a fall back you can try the
     9 # remarked out baseurl= line instead.
      10 #
      11 #

      12 [base]
      13 name=CentOS-$releasever - Base - 163.com
      14 baseurl=http://mirrors.163.com/centos/6.9/os/$basearch/
      15 #mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os
      16 gpgcheck=1
      17 gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6
       
      18 #released updates
      19 [updates]
      20 name=CentOS-$releasever - Updates - 163.com
      21 baseurl=http://mirrors.163.com/centos/6.9/updates/$basearch/
      22 #mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=updates
      23 gpgcheck=1
      24 gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6
       
      25 #additional packages that may be useful
      26 [extras]
      27 name=CentOS-$releasever - Extras - 163.com
      28 baseurl=http://mirrors.163.com/centos/6.9/extras/$basearch/
      29 #mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=extras
      30 gpgcheck=1
      31 gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6
       
      32 #additional packages that extend functionality of existing packages
      33 [centosplus]
      34 name=CentOS-$releasever - Plus - 163.com
      35 baseurl=http://mirrors.163.com/centos/6.9/centosplus/$basearch/
      36 #mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=centosplus
      37 gpgcheck=1
      38 enabled=0
      39 gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6
       
      40 #contrib - packages by Centos Users
      41 [contrib]
      42 name=CentOS-$releasever - Contrib - 163.com
      43 baseurl=http://mirrors.163.com/centos/6.9/contrib/$basearch/
      44 #mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=contrib
      45 gpgcheck=1
      46 enabled=0
      47 gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6

5 测试

      1.清理一下缓存：

          yum clean all

                   2.做个本地缓存，搜索起来会快很多

          yum makecache 

                  3.列出已安装的软件包

           yum list

      如果前三步能够正常执行，那基本上已经配置好了，接下来就愉快的折腾吧！

                 4.享受一下劳动成果

        yum update

             RHEL6.9换源记到此已经结束喽，希望可以帮助到大家。本文还有诸多不足之处，望各位大佬多多指点！

               本文参考了http://www.thinkphp.cn/topic/34712.html。