CentOS-5的yum源无法使用问题

[root@37wan ~]# yum -y install gcc

Loaded plugins: fastestmirror

Determining fastest mirrors

YumRepo Error: All mirror URLs are not using ftp, http[s] or file.

 Eg. Invalid release/

removing mirrorlist with no valid mirrors: /var/cache/yum/base/mirrorlist.txt

Error: Cannot find a valid baseurl for repo: base

可以看出：URLs不是ftp或http地址，打开yum查看：

[base]

name=CentOS-$releasever - Base

mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os

#baseurl=http://mirror.centos.org/centos/$releasever/os/$basearch/

gpgcheck=1

gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5

[root@ yum.repos.d]# wget mirrorlist=http://mirrorlist.centos.org/6release=$releasever&arch=$basearch&repo=os

[1] 4853

[2] 4854

[root@ yum.repos.d]# mirrorlist=http://mirrorlist.centos.org/6release=: Unsupported scheme.  

即源的网址有问题。
更新文件内容，用以下内容替换：

# 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-$releasever - Base

#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os

#baseurl=http://mirror.centos.org/centos/$releasever/os/$basearch/

baseurl=http://vault.centos.org/5.11/os/$basearch/

gpgcheck=1

gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5  

#released updates

[updates]

name=CentOS-$releasever - Updates

#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=updates

#baseurl=http://mirror.centos.org/centos/$releasever/updates/$basearch/

baseurl=http://vault.centos.org/5.11/updates/$basearch/

gpgcheck=1

gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5  

#additional packages that may be useful

[extras]

name=CentOS-$releasever - Extras

#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=extras

#baseurl=http://mirror.centos.org/centos/$releasever/extras/$basearch/

baseurl=http://vault.centos.org/5.11/extras/$basearch/

gpgcheck=1

gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5  

#additional packages that extend functionality of existing packages

[centosplus]

name=CentOS-$releasever - Plus

#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=centosplus

#baseurl=http://mirror.centos.org/centos/$releasever/centosplus/$basearch/

baseurl=http://vault.centos.org/5.11/centosplus/$basearch/

gpgcheck=1

enabled=0

gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5  

#contrib - packages by Centos Users

[contrib]

name=CentOS-$releasever - Contrib

#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=contrib

#baseurl=http://mirror.centos.org/centos/$releasever/contrib/$basearch/

baseurl=http://vault.centos.org/5.11/contrib/$basearch/

gpgcheck=1

enabled=0

gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5</span></strong></span>

修改文件后，清空yum源缓存：
yum clean all #清空yum源缓存
yum makecache #从新加载新缓存

用国内的yum源会出现一下问题，用上述解决办法，也ok，虽然会有一个连接报错

http://mirrors.aliyun.com/centos/5/os/x86_64/repodata/repomd.xml: [Errno 14] HTTP Error 404: Not Found

用浏览器打开http://mirrors.aliyun.com/centos/5/os/x86_64/repodata/repomd.xml，根本找不到这个文件，163……也是，但是Centos6内有,说明国内也不知Centos5了！