1.卸载rhel的默认安装的yum包查看yum包rpm -qa|grep yum卸载之rpm -qa|grep yum|xargs rpm -e --nodeps
2.下载新的yum包64位linux系统下载安装包wget http://centos.ustc.edu.cn/centos/5/os/x86_64/CentOS/yum-3.2.22-40.el5.centos.noarch.rpmwget http://centos.ustc.edu.cn/centos/5/os/x86_64/CentOS/yum-fastestmirror-1.1.16-21.el5.centos.noarch.rpmwget http://centos.ustc.edu.cn/centos/5/os/x86_64/CentOS/yum-metadata-parser-1.1.2-4.el5.x86_64.rpm32位linux系统下载安装包wget http://centos.ustc.edu.cn/centos/5/os/i386/CentOS/yum-3.2.22-40.el5.centos.noarch.rpmwget http://centos.ustc.edu.cn/centos/5/os/i386/CentOS/yum-fastestmirror-1.1.16-21.el5.centos.noarch.rpmwget http://centos.ustc.edu.cn/centos/5/os/i386/CentOS/yum-metadata-parser-1.1.2-4.el5.i386.rpm注意：安装包可能会升级，最后的文件名可以通过最新路径下查看得到，例如：http://centos.ustc.edu.cn/centos/5/os/x86_64/CentOS/http://centos.ustc.edu.cn/centos/5/os/i386/CentOS/然后进行安装rpm -ivh yum-*注意：yum和yum-fastestmirror相互依赖，所以同时安装即可。