RedHat自带的yum因为未注册不能使用，我们用CentOS的yum替代之。
以下的路径注意是否还存在，不存在的话可以使用其他mirrors，或者进入
http://mirrors.163.com/centos/ 查找一下
可以使用搜狐提供的开源镜像
mirrors.sohu.com
更多镜像参考
http://lannerk.iteye.com/blog/2068356
下载
wget http://mirrors.163.com/centos/6/os/x86_64/Packages/yum-3.2.29-40.el6.centos.noarch.rpm wget http://mirrors.163.com/centos/6/os/x86_64/Packages/yum-metadata-parser-1.1.2-16.el6.x86_64.rpm wget http://mirrors.163.com/centos/6/os/x86_64/Packages/yum-plugin-fastestmirror-1.1.30-14.el6.noarch.rpm wget http://mirrors.163.com/centos/6/os/x86_64/Packages/python-iniparse-0.3.1-2.1.el6.noarch.rpm
进行安装yum
rpm -ivh python-iniparse-0.3.1-2.1.el6.noarch.rpm rpm -ivh yum-metadata-parser-1.1.2-16.el6.x86_64.rpm rpm -ivh yum-3.2.29-40.el6.centos.noarch.rpm yum-plugin-fastestmirror-1.1.30-14.el6.noarch.rpm
更新repo文件
去掉/etc/yum.repos.d/ 下的文件，备份起来
vi /etc/yum.repos.d/rhel-debuginfo.repo
加入以下内容
[base] name=CentOS-$releasever - Base baseurl=http://mirrors.163.com/centos/6/os/$basearch/ gpgcheck=1 gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-6 #released updates [updates] name=CentOS-$releasever - Updates baseurl=http://mirrors.163.com/centos/6/updates/$basearch/ gpgcheck=1 gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-6 #packages used/produced in the build but not released #[addons] #name=CentOS-$releasever - Addons #baseurl=http://mirrors.163.com/centos/$releasever/addons/$basearch/ #gpgcheck=1 #gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-6 #additional packages that may be useful [extras] name=CentOS-$releasever - Extras baseurl=http://mirrors.163.com/centos/6/extras/$basearch/ gpgcheck=1 gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-6 #additional packages that extend functionality of existing packages [centosplus] name=CentOS-$releasever - Plus baseurl=http://mirrors.163.com/centos/6/centosplus/$basearch/ gpgcheck=1 enabled=0
生效
yum clean all
测试
yum install -y gcc gcc-c++