在RedHat系统上使用yum指令时出现如下问题：
“The system is not registered with RHN”的原因是没有在红帽网络上注册，解决方法改为使用CentOS的yum源。
1.查看rhel默认安装的yum包，并卸载
- [root@zhu1 ~]# rpm -qa | grep yum
- yum-fastestmirror-1.1.16-14.el5.centos.1
- yum-updatesd-0.9-2.el5
- yum-metadata-parser-1.1.2-3.el5.centos
- yum-3.2.22-40.el5.centos
- [root@zhu1 ~]# rpm -qa | grep yum |xargs rpm -e --nodeps
2.下载centos的yum包
- [root@zhu1 ~]#wget http://centos.ustc.edu.cn/centos/5/os/i386/CentOS/yum-3.2.22-40.el5.centos.noarch.rpm
- [root@zhu1 ~]#wget http://centos.ustc.edu.cn/centos/5/os/i386/CentOS/yum-fastestmirror-1.1.16-21.el5.centos.noarch.rpm
- [root@zhu1 ~]#wget http://centos.ustc.edu.cn/centos/5/os/i386/CentOS/yum-metadata-parser-1.1.2-4.el5.i386.rpm
- #安装
- [root@zhu1 ~]# rpm -ivh yum-*
3.下载新的yum源放到/etc/yum.repos.d/目录下
- [root@zhu1 ~]# wget http://www.linuxidc.com/files/2011/05/06/CentOS-Base.repo
