新安装了redhat6.5.安装后，登录系统，使用yum update 更新系统。提示：
Loaded plugins: product-id, security, subscription-manager
This system is not registered to Red Hat Subscription Management. You can us e subscription-manager to register.
1.删除redhat自带的yum包
[root@localhost ~]# rpm -qa |grep yum |xargs rpm -e --nodeps
[root@localhost ~]# rpm -qa |grep yum
2.下载新的yum包。使用Centos6.5的yum包
1)查看系统类别
root@localhost ~]# cat /etc/redhat-release
Red Hat Enterprise Linux Server release 6.5 (Santiago)
2)下载新的yum包。使用Centos6.5的yum包
[root@localhost ~]# wget http://mirrors.163.com/centos/6/os/x86_64/Packages/yum-metadata-parser-1.1.2-16.el6.x86_64.rpm
[root@localhost ~]# wget http://mirrors.163.com/centos/6/os/x86_64/Packages/yum-3.2.29-81.el6.centos.noarch.rpm
[root@localhost ~]# wget http://mirrors.163.com/centos/6/os/x86_64/Packages/yum-plugin-fastestmirror-1.1.30-41.el6.noarch.rpm
[root@localhost ~]# wget http://mirrors.163.com/centos/6/os/x86_64/Packages/python-urlgrabber-3.9.1-11.el6.noarch.rpm
3)安装
[root@localhost ~]# rpm -ivh yum-metadata-parser-1.1.2-16.el6.x86_64.rpm yum-3.2.29-81.el6.centos.noarch.rpm yum-plugin-fastestmirror-1.1.30-41.el6.noarch.rpm python-urlgrabber-3.9.1-11.el6.noarch.rpm
warning: yum-metadata-parser-1.1.2-16.el6.x86_64.rpm: Header V3 RSA/SHA1 Signature, key ID c105b9de: NOKEY
Preparing... ########################################### [100%]
file /usr/lib/python2.6/site-packages/urlgrabber/grabber.py from install of python-urlgrabber-3.9.1-11.el6.noarch conflicts with file from package python-urlgrabber-3.9.1-9.el6.noarch
file /usr/lib/python2.6/site-packages/urlgrabber/grabber.pyc from install of python-urlgrabber-3.9.1-11.el6.noarch conflicts with file from package python-urlgrabber-3.9.1-9.el6.noarch
file /usr/lib/python2.6/site-packages/urlgrabber/grabber.pyo from install of python-urlgrabber-3.9.1-11.el6.noarch conflicts with file from package python-urlgrabber-3.9.1-9.el6.noarch
file /usr/lib/python2.6/site-packages/urlgrabber/progress.pyc from install of python-urlgrabber-3.9.1-11.el6.noarch conflicts with file from package python-urlgrabber-3.9.1-9.el6.noarch
file /usr/lib/python2.6/site-packages/urlgrabber/progress.pyo from install of python-urlgrabber-3.9.1-11.el6.noarch conflicts with file from package python-urlgrabber-3.9.1-9.el6.noarch
[root@localhost ~]# file /usr/lib/python2.6/site-packages/urlgrabber/grabber.py from install of python-urlgrabber-3.9.1-11.el6.noarch conflicts with file from package python-urlgrabber-3.9.1-9.el6.noarch
报错
查找问题，是python-urlgrabber引起的，要删除掉旧的包
rpm -e python-urlgrabber-3.9.1-9.el6.noarch
安装 rpm -ivh python-urlgrabber-3.9.1-11.el6.noarch.rpm
再安装
[root@localhost ~]# rpm -ivh yum-metadata-parser-1.1.2-16.el6.x86_64.rpm yum-3.2.29-81.el6.centos.noarch.rpm yum-plugin-fastestmirror-1.1.30-41.el6.noarch.rpm
warning: yum-metadata-parser-1.1.2-16.el6.x86_64.rpm: Header V3 RSA/SHA1 Signature, key ID c105b9de: NOKEY
Preparing... ########################################### [100%]
1:yum-metadata-parser ########################################### [ 33%]
2:yum-plugin-fastestmirro########################################### [ 67%]
3:yum ########################################### [100%]
[root@localhost ~]#
4）更换yum源，将原有源删除或备份到别的目下下：
#cd /etc/yum.repos.d/
#wget http://mirrors.163.com/.help/CentOS6-Base-163.repo
#vi CentOS6-Base-163.repo
编辑文件，把文件里面的$releasever全部替换为版本号：6（注意，不是6.5！）最后保存！
#yum clean all
#yum makecache
参考资源:
http://blog.sina.com.cn/s/blog_439628be0102woxd.html
https://blog.csdn.net/zhaihaifei/article/details/54616840