一，建立一个yum仓库，建立服务端

1，建立一个目录/export/yum/Server
2, 拷贝rpm到这个目录

3，安装createrepo
[root@localhost Server]# rpm -ivh createrepo-0.4.4-2.fc6.noarch.rpm
warning: createrepo-0.4.4-2.fc6.noarch.rpm: Header V3 DSA signature: NOKEY, key ID 37017186
Preparing... ########################################### [100%]
1:createrepo ########################################### [100%]
[root@localhost yum]#

4，执行：
[root@localhost Server]# createrepo -v /export/yum/Server
1/2158 - libbtctl-0.6.0-9.2.el5.i386.rpm
2/2158 - man-pages-cs-0.16-6.noarch.rpm

5，配置一下httpd服务
做链接文件：
[root@localhost html]# pwd
/var/www/html
[root@localhost html]# ln -s /export/ ./

重新启动httpd服务
[root@localhost html]# service httpd restart
Stopping httpd: [ OK ]
Starting httpd: [ OK ]
[root@localhost html]#

6，客户端清除yum缓存信息：
[root@localhost ~]# yum clean dbcache
Loading "security" plugin
Loading "rhnplugin" plugin
Loading "installonlyn" plugin
This system is not registered with RHN.
RHN support will be disabled.
0 cache files removed
[root@localhost ~]#

二，建立yum客户端配置文件
create a file in /etc/yum.repos.d for your repository
文件内容：
[tonykorn97]
name=tonykorn97 yum server
baseure=http://172.25.1.141/export/yum/Server
enabled=1
gpgcheck=0

更新的时候提示：
[root@localhost yum.repos.d]# yum list httpd
Loading "security" plugin
Loading "rhnplugin" plugin
Loading "installonlyn" plugin
This system is not registered with RHN.
RHN support will be disabled.
Setting up repositories
Error: Cannot find a valid baseurl for repo: tonykorn97
[root@localhost yum.repos.d]#

更改为就内容为：
[tonykorn97]
name=tonykorn97 yum server
baseure=file:///export/yum/Server
enabled=1
gpgcheck=0

一样的结果。

发现是baseurl写错成baseure了，更改过来后就可以了。