CentOS yum不能用

修改/etc/yum.repos.d/Centos-Base.repo

# 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-$releasever - Base - 163.combaseurl=http://mirrors.163.com/centos/$releasever/os/$basearch/#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=osgpgcheck=1gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6#released updates [updates]name=CentOS-$releasever - Updates - 163.combaseurl=http://mirrors.163.com/centos/$releasever/updates/$basearch/#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=updatesgpgcheck=1gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6#additional packages that may be useful[extras]name=CentOS-$releasever - Extras - 163.combaseurl=http://mirrors.163.com/centos/$releasever/extras/$basearch/#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=extrasgpgcheck=1gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6#additional packages that extend functionality of existing packages[centosplus]name=CentOS-$releasever - Plus - 163.combaseurl=http://mirrors.163.com/centos/$releasever/centosplus/$basearch/#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=centosplusgpgcheck=1enabled=0gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6#contrib - packages by Centos Users[contrib]name=CentOS-$releasever - Contrib - 163.combaseurl=http://mirrors.163.com/centos/$releasever/contrib/$basearch/#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=contribgpgcheck=1enabled=0gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-CentOS-6

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centos /etc/yum.repo.d/中.repo源的配置与编写详解 

# 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]                     //唯一标识的名称
name=CentOS-$releasever - Base    //所使用的.repo文件的名字
mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os

#mirrorlist 是由 yum 程式自行去捉映射站台， baseurl 则是指定固定的一個容器网址

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

#其中url支持的协议有 http:// ftp:// file://三种。baseurl后可以跟多个url，你可以自己改为速度比较快的镜像站，但baseurl只能有一个

gpgcheck=1       #gpg签名检查
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5        

#gpg密钥的位置，应指定本机的密钥文件只有可以与服务器上的密钥进行校验。

#released updates

#该段指向的路径是软件升级时需要的软件包

[updates]
name=CentOS-$releasever - Updates
mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=updates

//该路径对应服务器上的update文件夹，即自动到服务器updates文件夹里找软件包

#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

#该段指向的路径是已经使用了或者已经制作出来的软件，但并没有发行

[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

#该段指向的路径是可能有用的其他的软件

[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

#该段指向的路径是已经存在的软件的扩展软件、插件等等

[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               #enabled=0表示这个源停用 如果enabled不写 表示enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5

#contrib - packages by Centos Users

#该段指向的路径是系统使用者所贡献的软件

[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