1. 检查系统已安装的组件包中是否已存在Redhat的自带的yum系列组件包
# su root
# rpm -qa | grep yum
2. 如果存在请逐一全部删除
# rpm -e --nodeps 组件包名称
3. 安装Centos升级组件包
# su root
# rpm -Uvh --nodeps *.rpm
wget http://mirrors.163.com/centos/5.5/os/i386/CentOS/python-iniparse-0.2.3-4.el5.noarch.rpm
wget http://mirrors.163.com/centos/5.5/os/i386/CentOS/yum-3.2.22-26.el5.centos.noarch.rpm
wget http://mirrors.163.com/centos/5.5/os/i386/CentOS/yum-fastestmirror-1.1.16-14.el5.centos.1.noarch.rpm
wget http://mirrors.163.com/centos/5.5/os/i386/CentOS/yum-metadata-parser-1.1.2-3.el5.centos.i386.rpm
4. 创建并编辑yum升级源配置文件
# su root
# mkdir -p /etc/yum.repos.d/
# vi /etc/yum.repos.d/CentOS-Base.repo
[base] name=CentOS-$releasever - Base baseurl=http://mirrors.163.com/centos/5.5/os/$basearch/ gpgcheck=1 gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-5 #released updates [update] name=CentOS-$releasever - Updates baseurl=http://mirrors.163.com/centos/5.5/updates/$basearch/ gpgcheck=1 gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-5 #packages used/produced in the build but not released [addons] name=CentOS-$releasever - Addons baseurl=http://mirrors.163.com/centos/5.5/addons/$basearch/ gpgcheck=1 gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-5 #additional packages that may be useful [extras] name=CentOS-$releasever - Extras baseurl=http://mirrors.163.com/centos/5.5/extras/$basearch/ gpgcheck=1 gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-5 #additional packages that extend functionality of existing packages [centosplus] name=CentOS-$releasever - Plus baseurl=http://mirrors.163.com/centos/5.5/centosplus/$basearch/ gpgcheck=1 enabled=0 gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-5 #contrib - packages by Centos Users [contrib] name=CentOS-$releasever - Contrib baseurl=http://mirrors.163.com/centos/5.5/contrib/$basearch/ gpgcheck=1 enabled=0 gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-5
5. yum update
6. 安装fedora的包
在CentOS上安装Git非常方便，可以安装EPEL，这是一个由Fedora 社区打造，由为RHEL及衍生发行版提供高质量软件的项目，里面有软件还是比较丰富的，默认的没有git。。。。我的CentOS版本是5.5，执行下面命令安装该库：
sudo rpm –Uvh http://download.fedora.redhat.com/pub/epel/5/i386/epel-release-5-4.noarch.rpm
