根据需要选择设置源：
一、如何设置CentOS
5的yum源为上海交通大学网站
二、设置yum源为国内的服务器
三、CentOS 下使用本地镜像源
一。如何设置CentOS
5的yum源为上海交通大学网站
1．修改/etc/yum.repos.d/CentOS-Base.repo为:
CentOS-Base.repo
[base]
name=CentOS-5 - Base
#mirrorlist=
repo=os
#baseurl=
baseurl=
gpgcheck=1
gpgkey=
#released updates
[update]
name=CentOS-5 - Updates
#mirrorlist=
baseurl=
gpgcheck=1
gpgkey=
#packages used/produced in the
build but not released
[addons]
name=CentOS-5 - Addons
#mirrorlist=
baseurl=
gpgcheck=1
gpgkey=
#additional packages that may
be useful
[extras]
name=CentOS-5 - Extras
#mirrorlist=
baseurl=
gpgcheck=1
gpgkey=
#additional packages that
extend functionality of existing packages
[centosplus]
name=CentOS-5 - Plus
#mirrorlist=
baseurl=
gpgcheck=1
enabled=0
gpgkey=
#contrib - packages by Centos
Users
[contrib]
name=CentOS-5 - Contrib
#mirrorlist=
baseurl=
gpgcheck=1
enabled=0
gpgkey=
2．执行
64位：
rpm --import
32位：
rpm --import
3．执行
yum update
Ok了，搞定。
二、设置yum源为国内的服务器：
1.相关需更改配置文件位置同上。
#
CentOS-Base.repo
#
# This file uses a new
mirrorlist system developed by Lance Davis for CentOS.
# The mirror system uses the
connecting IP address of the client and the
# update status of each mirror
to pick mirrors that are updated to and
# geographically close to the
client. You should use this for CentOS updates
# unless you are manually
picking other mirrors.
#
# If the mirrorlist= does not
work for you, as a fall back you can try the
# remarked out baseurl= line
instead.
#
[base]
name=CentOS-5 -
Base
baseurl=
gpgcheck=1
#released updates
[update]
name=CentOS-5 -
Updates
baseurl=
gpgcheck=1
#packages used/produced in the
build but not released
[addons]
name=CentOS-5 -
Addons
baseurl=
gpgcheck=1
#additional packages that may
be useful
[extras]
name=CentOS-5 -
Extras
baseurl=
gpgcheck=1
#additional packages that
extend functionality of existing packages
[centosplus]
name=CentOS-5 -
Plus
baseurl=
gpgcheck=1
enabled=0
#contrib - packages by Centos
Users
[contrib]
name=CentOS-5 -
Contrib
baseurl=
gpgcheck=1
enabled=0
#packages in
testing
[testing]
name=CentOS-5 -
Testing
baseurl=
gpgcheck=1
enabled=0
2.rpm --import
三、CentOS 下使用本地镜像源
不知道大家有没有和我一样尝试使用rsync
同步mirrors.kernel.org/CentOS，总计超过6G的数据在只有30-50KB/s的速度下传输，也许需要3-5天才可以完成。怎么办？使用国内的服务器吧，但是他们只提供yum源更新，也就是只能使用http访问，而不提供rsync
server。
这是我找到的一个速度不错的CentOS 4/5
yum源:218.201.144.68
使用wget将centos
5镜像到本地磁盘上
mkdir -pv
/opt/CentOS
cd /opt/CentOS
wget -m -c
以上命令会从网络上抓取2.6G左右的数据，会运行很长时间，你完全可以去做其它的工作。完成后，使用ls命令看看我们获取到的数据，我们只需要保留i386目录下面的数据，将其移动到opt，并将下载时产生的index.html?之类文件一并删除
cd
/opt/CentOS/218.201.144.68/centos/5/os/
mv i386
/opt/CentOS5
cd /opt
rm -rf CentOS
find CentOS5 -name
index.htm?\* -exec rm -f{}\;
下一步配置yum更新源。CentOS已经在/etc/yum.repos.d下面创建了CentOS-Media.repo，对该文件做适应修改就可以使用。以下是修改结果
[root@localhost etc]# cat
yum.repos.d/CentOS-Media.repo
#
CentOS-Media.repo
#
# This repo is used to mount
the default locations for a CDROM / DVD on
# CentOS-5. You can use this
repo and yum to install items directly off the
# DVD ISO that we
release.
#
# To use this repo, put in
your DVD and use it with the other repos too:
# yum --enablerepo=c4-media
[command]
#
# or for ONLY the media repo,
do this:
#
# yum --disablerepo=\*
--enablerepo=c4-media [command]
[c5-media]
name=CentOS-$releasever -
Media
baseurl=file:///opt/CentOS
#
file:///media/cdrom/
#
file:///media/cdrecorder/
gpgcheck=1
enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-beta
现在就可以使用yum
check-update来测验一下本地源了。如果在没有连接网络情况，最好把yum.repos.d目录下面的其它repo文件适当更名，这样yum就只使用本地源，速度得以提升。
本文出自 “聆听未来” 博客，请务必保留此出处http://blog.chinaunix.net/space.php?uid=9419692&do=blog&id=3182661
