本源是http://mirrors.163.com的,也可用http://centos.ustc.edu.cn/的,

或者http://mirrors.sohu.com/的。


经过分析
CentOS 5至CentOs 5.7可以用同一个源,  同样可以用到相应的RHEL版本
CentOS 5.8用另一个源,其软件版本更新,同样可以用到相应的RHEL版本

CentOS 5至CentOs 5.7如下
# CentOS-Base.repo
#
# 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
#mirrorlist=http://mirrorlist.centos.org/?release=5&arch=$basearch&repo=os
baseurl=http://mirrors.163.com/centos/5/os/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/5/os/x86_64/RPM-GPG-KEY-CentOS-5

#released updates
[updates]
name=CentOS-5 - Updates
#mirrorlist=http://mirrorlist.centos.org/?release=5&arch=$basearch&repo=updates
baseurl=http://mirrors.163.com/centos/5/updates/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/5/os/x86_64/RPM-GPG-KEY-CentOS-5

#additional packages that may be useful
[extras]
name=CentOS-5 - Extras
#mirrorlist=http://mirrorlist.centos.org/?release=5&arch=$basearch&repo=extras
baseurl=http://mirrors.163.com/centos/5/extras/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/5/os/x86_64/RPM-GPG-KEY-CentOS-5

#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-5 - Plus
#mirrorlist=http://mirrorlist.centos.org/?release=5&arch=$basearch&repo=centosplus
baseurl=http://mirrors.163.com/centos/5/centosplus/$basearch/
gpgcheck=1
enabled=1
gpgkey=http://mirrors.163.com/centos/5/os/x86_64/RPM-GPG-KEY-CentOS-5

#contrib - packages by Centos Users
[contrib]
name=CentOS-5 - Contrib
#mirrorlist=http://mirrorlist.centos.org/?release=5&arch=$basearch&repo=contrib
baseurl=http://mirrors.163.com/centos/5/contrib/$basearch/
gpgcheck=1
enabled=1
gpgkey=http://mirrors.163.com/centos/5/os/x86_64/RPM-GPG-KEY-CentOS-5


CentOS 5.8如下
# CentOS-Base.repo
#
# 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-5.8 - Base
#mirrorlist=http://mirrorlist.centos.org/?release=5&arch=$basearch&repo=os
baseurl=http://mirrors.163.com/centos/5.8/os/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/5.8/os/x86_64/RPM-GPG-KEY-CentOS-5

#released updates
[updates]
name=CentOS-5.8 - Updates
#mirrorlist=http://mirrorlist.centos.org/?release=5&arch=$basearch&repo=updates
baseurl=http://mirrors.163.com/centos/5.8/updates/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/5.8/os/x86_64/RPM-GPG-KEY-CentOS-5

#additional packages that may be useful
[extras]
name=CentOS-5.8 - Extras
#mirrorlist=http://mirrorlist.centos.org/?release=5&arch=$basearch&repo=extras
baseurl=http://mirrors.163.com/centos/5.8/extras/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/5.8/os/x86_64/RPM-GPG-KEY-CentOS-5

#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-5.8 - Plus
#mirrorlist=http://mirrorlist.centos.org/?release=5&arch=$basearch&repo=centosplus
baseurl=http://mirrors.163.com/centos/5.8/centosplus/$basearch/
gpgcheck=1
enabled=1
gpgkey=http://mirrors.163.com/centos/5.8/os/x86_64/RPM-GPG-KEY-CentOS-5

#contrib - packages by Centos Users
[contrib]
name=CentOS-5.8 - Contrib
#mirrorlist=http://mirrorlist.centos.org/?release=5&arch=$basearch&repo=contrib
baseurl=http://mirrors.163.com/centos/5.8/contrib/$basearch/
gpgcheck=1
enabled=1
gpgkey=http://mirrors.163.com/centos/5.8/os/x86_64/RPM-GPG-KEY-CentOS-5

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