今天需要用CentOS5.5测试个东西，但是发现在运行yum命令的时候出现下面的错误
Loaded plugins: allowdowngrade,downloadonly,fastestmirror Determining fastest mirrors Error: Cannot find a valid baseurl for repo: addons 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/addons/mirrorlist.txt
出现这个问题的原因CentOS5版本太老，官方不再维护了，所以yum默认配置文件中的url不能再使用。
因此，需要把/etc/yum.repos.d/CentOS-Base.repo文件中的url修改了
下面是修改前的配置
# 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-$releasever - Base mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os #baseurl=http://mirror.centos.org/centos/$releasever/os/$basearch/ gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5 #released updates [updates] name=CentOS-$releasever - Updates mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=updates #baseurl=http://mirror.centos.org/centos/$releasever/updates/$basearch/ gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5 #packages used/produced in the build but not released [addons] name=CentOS-$releasever - Addons mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=addons #baseurl=http://mirror.centos.org/centos/$releasever/addons/$basearch/ gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5 #additional packages that may be useful [extras] name=CentOS-$releasever - Extras mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=extras #baseurl=http://mirror.centos.org/centos/$releasever/extras/$basearch/ 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/$basearch/ gpgcheck=1 enabled=0 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5 #contrib - packages by Centos Users [contrib] name=CentOS-$releasever - Contrib mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=contrib #baseurl=http://mirror.centos.org/centos/$releasever/contrib/$basearch/ gpgcheck=1 enabled=0 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5
下面是修改后的配置
# 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-5.9 - Base #mirrorlist=http://mirrorlist.centos.org/?release=5.9&arch=$basearch&repo=os baseurl=http://vault.centos.org/5.9/os/$basearch/ gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5 #released updates [updates] name=CentOS-5.9 - Updates #mirrorlist=http://mirrorlist.centos.org/?release=5.9&arch=$basearch&repo=updates baseurl=http://vault.centos.org/5.9/updates/$basearch/ gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5 #packages used/produced in the build but not released [addons] name=CentOS-5.9 - Addons #mirrorlist=http://mirrorlist.centos.org/?release=5.9&arch=$basearch&repo=addons baseurl=http://vault.centos.org/5.9/addons/$basearch/ gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5 #additional packages that may be useful [extras] name=CentOS-5.9 - Extras #mirrorlist=http://mirrorlist.centos.org/?release=5.9&arch=$basearch&repo=extras baseurl=http://vault.centos.org/5.9/extras/$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-5.9 - Plus #mirrorlist=http://mirrorlist.centos.org/?release=5.9&arch=$basearch&repo=centosplus baseurl=http://vault.centos.org/5.9/centosplus/$basearch/ gpgcheck=1 enabled=0 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5 #contrib - packages by Centos Users [contrib] name=CentOS-5.9 - Contrib #mirrorlist=http://mirrorlist.centos.org/?release=5.9&arch=$basearch&repo=contrib baseurl=http://vault.centos.org/5.9/contrib/$basearch/ gpgcheck=1 enabled=0 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5
修改后，重新使用yum来安装包，一切可以正常工作了。
