Linux修改yum源免费使用CentOS源

在没有光盘的情况，需要安装软件包，就要用到共网的yum源来安装了。

RedHat linux 默认是安装了yum软件的，但是由于激活认证的原因让redhat无法直接进行yum安装一些软件，如果我们需要在redhat下直接yum安装软件，我们只用把yum的源修改成CentOS的就好了，然后把源里面的变量全部修改成实际的值，这样就能使用yum直接安装我们需要的软件了。

使用说明

1、到http://mirrors.163.com的 centos帮助文档 中下载CentOS6-Base-163.repo文件，存放到/etc/yum.repo.d中

Centos 5    wget  http://mirrors.163.com/.help/CentOS5-Base-163.repo

Centos 6    wget  http://mirrors.163.com/.help/CentOS6-Base-163.repo

操作如下：

2、首先备份/etc/yum.repos.d/CentOS-Base.repo

3、编辑CentOS6-Base-163.repo文件，将其中的$releasever更改为centos的版本号，如果是RedHat 6.2 X86_64为例“baseurl=http://mirrors.163.com/centos/6.2/os/x86_64/”，本文档是以RedHat 6.2 32位为例所写！

[base]

name=CentOS-6.2 - Base - 163.com

baseurl=http://mirrors.163.com/centos/6.2/os/$basearch/

#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os

gpgcheck=1

gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6.2

#released updates

[updates]

name=CentOS-6.2 - Updates - 163.com

baseurl=http://mirrors.163.com/centos/6.2/updates/$basearch/

#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=updates

gpgcheck=1

gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6.2

#additional packages that may be useful

[extras]

name=CentOS-6.2 - Extras - 163.com

baseurl=http://mirrors.163.com/centos/6.2/extras/$basearch/

#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=extras

gpgcheck=1

gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6.2

#additional packages that extend functionality of existing packages

[centosplus]

name=CentOS-6 .2- Plus - 163.com

baseurl=http://mirrors.163.com/centos/6.2/centosplus/$basearch/

#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=centosplus

gpgcheck=1

enabled=0

gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6.2

#contrib - packages by Centos Users

[contrib]

name=CentOS-6.2 - Contrib - 163.com

baseurl=http://mirrors.163.com/centos/6.2/contrib/$basearch/

#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=contrib

gpgcheck=1

enabled=0

gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6.2

编辑完后保存，运行：

yum clean all 清除原有缓存

yum makecache 获取yum列表