Centos5.11 使用yum源
由于我是用的系统是Centos 5.11以停止更新很多年，故此yum也不能用，找了很多方法，最终yum能稳定的运行在Centos5.11上，下面开始一一讲解步骤：
1：首先更新yum源
地址：http://vault.centos.org/
网站是有各个版本镜像的，所以 通过lsb_release -a查询下，系统版本如图
下面是我的yum源完整版本，下面会说出具体针对系统版本进行修改yum源方法：
vim /etc/yum.repos.d/Centos-Base.repo
# CentOS-Base.repo # # The mirror system uses the connecting IP address of the client and the # update status of each mirror to pick mirrors that are updated to and # geographically close to the client. You should use this for CentOS updates # unless you are manually picking other mirrors. # # If the mirrorlist= does not work for you, as a fall back you can try the # remarked out baseurl= line instead. # # [base] name=CentOS-$releasever - Base baseurl=http://vault.centos.org/5.11/os/x86_64/ gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5 #released updates [updates] name=CentOS-$releasever - Updates baseurl=http://vault.centos.org/5.11/os/x86_64/ gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5 #packages used/produced in the build but not released [addons] name=CentOS-$releasever - Addons baseurl=http://vault.centos.org/5.11/os/x86_64/ gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5 #additional packages that may be useful [extras] name=CentOS-$releasever - Extras baseurl=http://vault.centos.org/5.11/os/x86_64/ gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5 #additional packages that extend functionality of existing packages [centosplus] name=CentOS-$releasever - Plus baseurl=http://vault.centos.org/5.11/os/x86_64/ gpgcheck=1 enabled=0 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5 #contrib - packages by Centos Users [contrib] name=CentOS-$releasever - Contrib baseurl=http://vault.centos.org/5.11/os/x86_64/ gpgcheck=1 enabled=0 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5
注：如果你的版本是5.10（举例说明），打开此网站，http://vault.centos.org，根据上述地址http://vault.centos.org/5.11/os/x86_64/来进行修改，比如系统是5.10的话，是x86_64的，我们可以修改成http://vault.centos.org/5.10/os/x86_64/，修改完成后，浏览器打开输入地址，看看是不是可以显示出以下页面：
如果显示出上述页面，那根据我上面的5.11版本的Centos源把baseurl=http://vault.centos.org/5.11/os/x86_64/ 修改成 baseurl=http://vault.centos.org/5.10/os/x86_64/（是上述文件内容中，所有http://vault.centos.org/5.11/os/x86_64/地址），即可
修改完成后，保存，使用如下命令进行测试
yum clean all
yum makecache
测试成功后，可用yum进行安装、卸载软件
