This system is not registered with RHN. yum安装失败

使用RedHat 系统在线安装时提示This system is not registered with RHN.如下：

[root@localhost ~]# yum install httpd

Loaded plugins: rhnplugin, security

This system is not registered with RHN.

RHN support will be disabled.

Setting up Install Process

No package httpd available.

Nothing to do

解决方案：

1.卸载redhat自带的yum组件

[root@localhost ~]# rpm -qa|grep yum|xargs rpm -e --nodeps

2.重装yum

yum配置

[my]

name=my

gpgcheck=1

enabled=1

baseurl=file:///mnt/Server

gpgkey=file:///mnt/RPM-GPG-KEY-redhat-release