yum用不了，各位高手帮帮忙啊

davycu

好久没用过了，昨天用一下，发现不能用了，昨天搞了一夜没弄好，各位看看怎么解决啊？
出错信息如下：
[root@localhost davy]# yum update chmsee
Setting up Update Process
http://rpm.livna.org/fedora/Null/i386/repodata/repomd.xml: [Errno 12] Timeout: <urlopen error timed out>
Trying other mirror.
http://livna.cat.pdx.edu/fedora/Null/i386/repodata/repomd.xml: [Errno 4] IOError: <urlopen error (101, 'Network is unreachable')>
Trying other mirror.
http://wftp.tu-chemnitz.de/pub/l ... epodata/repomd.xml: [Errno 14] HTTP Error 404: Content-Type: text/html
Content-Length: 345
Date: Thu, 28 Feb 2008 12:25:21 GMT
Server: lighttpd/1.4.18

Trying other mirror.
http://ftp-stud.fht-esslingen.de ... epodata/repomd.xml: [Errno 14] HTTP Error 404: Content-Type: text/html
Content-Length: 345
Date: Thu, 28 Feb 2008 12:25:24 GMT
Server: lighttpd/1.4.18

Trying other mirror.
http://mirror.atrpms.net/livna/f ... epodata/repomd.xml: [Errno 14] HTTP Error 404: Date: Thu, 28 Feb 2008 12:27:02 GMT
Server: Apache/2.2.3 (Red Hat)
Content-Length: 323
Content-Type: text/html; charset=iso-8859-1

Trying other mirror.
ftp://mirrors.tummy.com/pub/rpm. ... epodata/repomd.xml: [Errno 4] IOError: [Errno ftp error] 550 Failed to change directory.
Trying other mirror.
Error: Cannot open/read repomd.xml file for repository: livna

davycu

1# PUT YOUR REPOS HERE OR IN separate files named file.repo
      2 # in /etc/yum.repos.d
      3
      4 [main]
      5 cachedir=/var/cache/yum
      6 debuglevel=2
      7 logfile=/var/log/yum.log
      8 pkgpolicy=newest
      9 distroverpkg=yellowdog-release
     10 tolerant=1
     11 exactarch=1
     12
     13 [base]
     14 name=Red Hat Enterprise AS release 4 Updates
     15 baseurl=http://ftp.chinalinuxpub.com/redhat/enterprise/os/i386/RedHat/
     16 gpgcheck=1
     17 gpgkey=http://ftp.chinalinuxpub.com/redhat/enterprise/RPM-GPG-KEY-linuxpub
     18
     19 [update]
     20 name=Red Hat Enterprise AS release 4 Updates
     21 baseurl=http://ftp.chinalinuxpub.com/redhat/enterprise/updates/4AS/
     22 gpgcheck=1
     23 gpgkey=http://ftp.chinalinuxpub.com/redhat/enterprise/RPM-GPG-KEY-linuxpub
     24
     25
------------------------------
这是我的/etc/yum.conf文件，各位指导下啊

yourfriend

yum install yum-fastestmirror 安装一个插件试试，不行的话，看看这里
http://www.fedorachina.cn/index.php/topic,524.0.html