修改CentOS yum源

解决在CentOS yum源下载慢的办法

最近在虚拟机下面安装了个CentOS 5.5，使用yum更新时发现下载速度异常慢。可以修改yum的配置文件，把其镜像指向国内的服务器即可。
方案一：
# cd /etc/yum.repos.d/
# mv CentOS-Base.repo CentOS-Base.repo.bak
# wget http://docs.linuxtone.org/soft/lemp/CentOS-Base.repo 方案二：
手段修改CentOS-Base.repo文件，将baseurl设置成baseurl=http://ftp.sjtu.edu.cn/centos/5/addons/$basearch/
详细配置如下：

[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=1

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=1

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=1

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=1

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=1

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=1

enabled=0

gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-centos5

导入 key
＃ rpm –import http://ftp.sjtu.edu.cn/centos/5/os/i386/RPM-GPG-KEY-CentOS-5 运行，测试
＃ yum update
全部删除临时文件
#yum clean all

原文地址：http://www.cnblogs.com/codebean/archive/2011/05/27/2059900.html