国内速度最快的centos5.4 yum(更新源

第一步：修改/etc/yum.repos.d/CentOS- Base.repo为:

[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/5.4/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=$basearch&repo=updates 
baseurl=http://ftp.sjtu.edu.cn/centos/5.4/updates/$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/5.4/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/5.4/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=$basearch&repo=centosplus 
baseurl=http://ftp.sjtu.edu.cn/centos/5.4/centosplus/$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=$basearch&repo=contrib 
baseurl=http://ftp.sjtu.edu.cn/centos/5.4/contrib/$basearch/ 
gpgcheck=1 
enabled=0 
gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-centos5

第二步：64位: rpm --import http://ftp.sjtu.edu.cn/centos/5.4/os/x86_64/RPM-GPG-KEY-CentOS-5
32位: rpm --import http://ftp.sjtu.edu.cn/centos/5.4/os/i386/RPM-GPG-KEY-CentOS-5
第三步：yum update