CentOS 5.5 更新yum源

[base]
name=CentOS-5 - Base
baseurl=
gpgcheck=1
gpgkey=

#released updates
[update]
name=CentOS-5 - Updates
baseurl=
gpgcheck=1
gpgkey=

#packages used/produced in the build but not released
[addons]
name=CentOS-5 - Addons
baseurl=
gpgcheck=1
gpgkey=
#additional packages that may be useful
[extras]
name=CentOS-5 - Extras
baseurl=
gpgcheck=1
gpgkey=

#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-5 - Plus
baseurl=
gpgcheck=1
enabled=0
gpgkey=

#contrib - packages by Centos Users
[contrib]
name=CentOS-5 - Contrib
baseurl=
gpgcheck=1
enabled=0
gpgkey=

#packages in testing
[testing]
name=CentOS-5 - Testing
baseurl=
gpgcheck=1
enabled=0
gpgkey=


保存退出
执行：
rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY*
yum upgrade

【删除 RHEL 自带的 yum】
# rpm -aq|grep yum|xargs rpm -e --nodeps