1、检查yum是否安装
rpm -qa |grep yum
2、利用CentOS的yum更新源来实现RHEL5的YUM功能
vi /etc/yum.repos.d/CentOS-Base.repo
[base] name=CentOS-5-Base #mirrorlist=http://mirrorlist.centos.org/?release=$releasever5&arch=$basearch&repo=os #baseurl=http://mirror.centos.org/centos/$releasever/os/$basearch/ baseurl=http://ftp.sjtu.edu.cn/centos/5/os/$basearch/ gpgcheck=0 gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-centos5 #released updates [update] name=CentOS-5-Updates #mirrorlist=http://mirrorlist.centos.org/?release=4&arch=$basearch&repo=updates baseurl=http://ftp.sjtu.edu.cn/centos/5/updates/$basearch/ gpgcheck=0 gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-centos5 #packages used/produced in the build but not released [addons] name=CentOS-5-Addons #mirrorlist=http://mirrorlist.centos.org/?release=4&arch=$basearch&repo=addons baseurl=http://ftp.sjtu.edu.cn/centos/5/addons/$basearch/ gpgcheck=0 gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-centos5 #additional packages that may be useful [extras] name=CentOS-5-Extras #mirrorlist=http://mirrorlist.centos.org/?release=4&arch=$basearch&repo=extras baseurl=http://ftp.sjtu.edu.cn/centos/5/extras/$basearch/ gpgcheck=0 gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-centos5 #additional packages that extend functionality of existing packages [centosplus] name=CentOS-5-Plus #mirrorlist=http://mirrorlist.centos.org/?release=4&arch=$basearch&repo=centosplus baseurl=http://ftp.sjtu.edu.cn/centos/5/centosplus/$basearch/ gpgcheck=0 enabled=0 gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-centos5 #contrib - packages by Centos Users [contrib] name=CentOS-5-Contrib #mirrorlist=http://mirrorlist.centos.org/?release=4&arch=$basearch&repo=contrib baseurl=http://ftp.sjtu.edu.cn/centos/5/contrib/$basearch/ gpgcheck=0 enabled=0 gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-centos5 # vi dag.repo [dag] name=Dag RPM Repository for RHEL5 baseurl=http://ftp.riken.jp/Linux/dag/redhat/el5/en/$basearch/dag/ enabled=1 gpgcheck=0 gpgkey=http://ftp.riken.jp/Linux/dag/packages/RPM-GPG-KEY.dag.txt
3、导入key
rpm --import http://ftp.sjtu.edu.cn/centos/5/os/i386/RPM-GPG-KEY-CentOS-5
4、运行YUM,测试