万网太恶心，装centos还要收费，默认的是as4.8，NND

只能使用以下的山寨方式更新。笔记之

as4 update8       
yum 安装
wget http://yum.baseurl.org/download/2.4/yum-2.4.3-1.src.rpm
rpmbuild –rebuild yum*.src.rpm
cd /usr/src/redhat/RPMS/noarch
rpm -ivh yum-2.4.3-1.noarch.rpm
vi /etc/yum.conf
加入以下内容：
”
[main]
cachedir=/var/cache/yum
debuglevel=2
logfile=/var/log/yum.log
pkgpolicy=newest
distroverpkg=redhat-release
tolerant=1
exactarch=1
obsoletes=1
# PUT YOUR REPOS HERE OR IN separate files named file.repo
# in /etc/yum.repos.d
#[base]
#name=Red Hat Linux $releasever – $basearch – Base
#baseurl=http://mirror.dulug.duke.edu/pub/yum-repository/redhat/$releasever/$basearch/
[base]
name=Red Hat Linux $releasever – $basearch – Base
baseurl=http://mirrors.163.com/centos/4.8/os/i386/
”
以上使用163的源

保存后
yum update
即可