二、重新配置yum相關文件
1、配置yum.conf,創建yum.conf文件，再進行編輯即可；
yum.conf內容，可直接拷貝，如下：
[main] cachedir=/var/cache/yum keepcache=1 debuglevel=2 logfile=/var/log/yum.log pkgpolicy=newest distroverpkg=redhat-release tolerant=1 exactarch=1 obsoletes=1 gpgcheck=1 plugins=1 metadata_expire=1800
粘貼完成後，保存後即可。可通過命令查看，是否一致。
2、配置rhel-debuginfo.repo,創建rhel-debuginfo.repo文件，再進行編輯即可（本文以CentOS5 64位地址為准）；
具體操作，同1，這裡只把內容展示如下：
[base] name=centos-5 - Base baseurl=http://centos.ustc.edu.cn/centos/5/os/x86_64/ # the other site: # you can find more site in: ?id=13 enabled=1 gpgcheck=1 gpgkey=http://centos.ustc.edu.cn/centos/5/os/x86_64/RPM-GPG-KEY-CentOS-5 #released updates [update] name=CentOS-5 - Updates baseurl=http://mirror.centos.org/centos/5/updates/x86_64/ gpgcheck=1 gpgkey=http://centos.ustc.edu.cn/centos/5/os/x86_64/RPM-GPG-KEY-CentOS-5 #packages used/produced in the build but not released [addons] name=CentOS-5 - Addons baseurl=http://mirror.centos.org/centos/5/addons/$basearch/ gpgcheck=1 gpgkey=http://centos.ustc.edu.cn/centos/5/os/x86_64/RPM-GPG-KEY-CentOS-5 #additional packages that may be useful [extras] name=CentOS-5 - Extras baseurl=http://mirror.centos.org/centos/5/extras/$basearch/ gpgcheck=1 gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-centos4 #additional packages that extend functionality of existing packages [centosplus] name=CentOS-5 - Plus baseurl=http://mirror.centos.org/centos/5/centosplus/$basearch/ gpgcheck=1 enabled=0 gpgkey=http://centos.ustc.edu.cn/centos/5/os/x86_64/RPM-GPG-KEY-CentOS-5 #contrib - packages by Centos Users [contrib] name=CentOS-5 - Contrib baseurl=http://mirror.centos.org/centos/5/contrib/$basearch/ gpgcheck=1 enabled=0 gpgkey=http://centos.ustc.edu.cn/centos/5/os/x86_64/RPM-GPG-KEY-CentOS-5 #packages in testing [testing] name=CentOS-5 - Testing baseurl=http://mirror.centos.org/centos/5/testing/$basearch/ gpgcheck=1 enabled=0 gpgkey=http://centos.ustc.edu.cn/centos/5/os/x86_64/RPM-GPG-KEY-CentOS-5