转自：http://inlhx.iteye.com/blog/2336729
RedHat 更换Yum源
1.检查yum包 rpm -qa |grep yum
2.删除自带包
rpm -aq | grep yum | xargs rpm -e --nodeps
3.再检查一下
rpm -qa |grep yum
4.下载更新包
wget
wget wget
wget
wget
wget
5.执行安装
rpm -ivh yum-*
如果出现
error: Failed dependencies:
python-urlgrabber >= 3.9.1-10 is needed by yum-3.2.29-73.el6.centos.noarch
不要慌，这个问题很恶心会导致后面安装前功尽弃，使用下面
rpm -Uvh python-urlgrabber-3.9.1-11.el6.noarch.rpm
更新rpm -Uvh python-urlgrabber版本，不更新肯定安装不过去
在执行：
rpm -ivh yum-*
warning: yum-3.2.29-73.el6.centos.noarch.rpm: Header V3 RSA/SHA1 Signature, key ID c105b9de: NOKEY
Preparing... ########################################### [100%]
1:yum-metadata-parser ########################################### [ 20%]
2:yum-plugin-fastestmirro########################################### [ 40%]
3:yum ########################################### [ 60%]
4:yum-updateonboot ########################################### [ 80%]
5:yum-utils ########################################### [100%]
安装成功了
6.切换源
cd /etc/yum.repos.d/
mv redhat.repo redhat.repo.bak
mv rhel-source.repo rhel-source.repo.bak
vi /etc/yum.repos.d/CentOS-Base.repo
粘贴如下信息：
#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-6 - Base - 163.com
#mirrorlist=http://mirrorlist.centos.org/?release=6&arch=$basearch&repo=os
baseurl=http://mirrors.163.com/centos/7/os/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-6.7
#released updates
[updates]
name=CentOS-6 - Updates - 163.com
#mirrorlist=http://mirrorlist.centos.org/?release=6&arch=$basearch&repo=updates
baseurl=http://mirrors.163.com/centos/7/updates/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-6.7
#additional packages that may be useful
[extras]
name=CentOS-6 - Extras - 163.com
#mirrorlist=http://mirrorlist.centos.org/?release=6&arch=$basearch&repo=extras
baseurl=http://mirrors.163.com/centos/7/extras/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-6.7
#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-6 - Plus - 163.com
baseurl=http://mirrors.163.com/centos/7/centosplus/$basearch/
gpgcheck=1
enabled=0
gpgkey=
8.清理缓存
yum clean all
yum makecache
9.验证
yum install telnet