引言：CentOS自带的yum源中rpm包数量有限，很多时候找不到我们需的软件包，(例如：要安装网络连接查看软件iftop，默认设置下无法使用yum命令安装)，下面教大家在CentOS 6.2中(以32位系统为例，64位系统安装方法一样)，使用第三方yum源来安装更多软件包。

一、安装CentOS yum源优先级插件yum-priorities

yum install yum-priorities   #输入y安装

二、设置CentOS默认yum源的优先级为最高系统运维  www.osyunwei.com  温馨提醒：qihang01原创内容©版权所有,转载请注明出处及原文链接

cd  /etc/yum.repos.d/   #进入yum源目录

vi CentOS-Base.repo    #在[base]、[updates]、[extras]组下面添加priority=1，在[centosplus]、[contrib]组下面添加priority=2

################################################################

[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-6

priority=1

[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-6

priority=1

[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-6

priority=1

[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-6

priority=2

[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-6

priority=2

###############################################################

备注：priority的优先级为1到99，设置为1即优先级最高，1-10为系统保留，第三方yum源的优先级从11-99

三、安装epel yum源

rpm -ivh  http://download.fedora.redhat.com/pub/epel/6/i386/epel-release-6-5.noarch.rpm

rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-6

vi /etc/yum.repos.d/epel.repo   #修改epel yum源优先级，priority=11

###############################################################

[epel]

name=Extra Packages for Enterprise Linux 6 - $basearch

#baseurl=http://download.fedoraproject.org/pub/epel/6/$basearch

mirrorlist=https://mirrors.fedoraproject.org/metalink?repo=epel-6&arch=$basearch

failovermethod=priority

enabled=1

gpgcheck=1

gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-6

priority=11

#################################################################

四、安装rpmforge yum源

wget http://apt.sw.be/redhat/el6/en/i386/rpmforge/RPMS/rpmforge-release-0.5.2-2.el6.rf.i686.rpm

wget http://dag.wieers.com/rpm/packages/RPM-GPG-KEY.dag.txt

rpm --import RPM-GPG-KEY.dag.txt

rpm -ivh rpmforge-release-0.5.2-2.el6.rf.i686.rpm

vi  /etc/yum.repos.d/rpmforge.repo  #修改rpmforge yum源优先级，priority=12

#################################################################

[rpmforge]

name = RHEL $releasever - RPMforge.net - dag

baseurl = http://apt.sw.be/redhat/el6/en/$basearch/rpmforge

mirrorlist = http://apt.sw.be/redhat/el6/en/mirrors-rpmforge

#mirrorlist = file:///etc/yum.repos.d/mirrors-rpmforge

enabled = 1

protect = 0

gpgkey = file:///etc/pki/rpm-gpg/RPM-GPG-KEY-rpmforge-dag

gpgcheck = 1

priority=12

#################################################################

系统运维  www.osyunwei.com  温馨提醒：qihang01原创内容©版权所有,转载请注明出处及原文链接

五、安装rpmfusion yum源

rpm -ivh http://download1.rpmfusion.org/free/el/updates/testing/6/i386/rpmfusion-free-release-6-0.1.noarch.rpm

vi  /etc/yum.repos.d/rpmfusion-free-updates-testing.repo   #修改rpmfusion yum源优先级，priority=13

#################################################################

[rpmfusion-free-updates-testing]

name=RPM Fusion for EL 6 - Free - Test Updates

#baseurl=http://download1.rpmfusion.org/free/el/updates/testing/6/$basearch/

mirrorlist=http://mirrors.rpmfusion.org/mirrorlist?repo=free-el-updates-testing-6&arch=$basearch

enabled=1

gpgcheck=1

gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-rpmfusion-free-el-6

priority=13

系统运维  www.osyunwei.com  温馨提醒：qihang01原创内容©版权所有,转载请注明出处及原文链接

#################################################################

六、安装atomic yum源

wget http://www.atomicorp.com/installers/atomic  #下载

sh ./atomic   #安装

vi  /etc/yum.repos.d/atomic.repo  #修改atomic yum源优先级，priority=14

##############################################################

[atomic]

name = CentOS / Red Hat Enterprise Linux $releasever - atomicrocketturtle.com

mirrorlist = http://www.atomicorp.com/mirrorlist/atomic/centos-6-$basearch

#mirrorlist = http://www.atomicorp.com/channels/atomic/centos/6/mirrors-atomic

enabled = 1

priority = 1

protect = 0

gpgkey = file:///etc/pki/rpm-gpg/RPM-GPG-KEY.art.txt

gpgcheck = 1

priority=14

##############################################################

七、更新yum软件包

yum check-update

八、安装iftop

yum install iftop

至此，CentOS 第三方yum源配置完成，现在你可以用yum命令安装自己需要的软件了！比如yum install nginx、yum update php等安装或者升级软件包。备注：以下两个第三方yum源可以使用

rpm -Uvh http://mirrors.ustc.edu.cn/fedora/epel/6/i386/epel-release-6-8.noarch.rpm

rpm -Uvh http://rpms.famillecollet.com/enterprise/remi-release-6.rpm

yum --enablerepo=remi install php

######################################################################################扩展阅读：在使用yum update php命令升级php的同时，mysql也被升级到了最新版，升级好之后重启mysql，有可能会出现下面的错误信息，导致mysql启动失败。

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)

解决方法(切记，操作前，一定备份mysql数据库)：

rm -fr /var/lib/mysql/*      #删除目录

rm /var/lock/subsys/mysqld   #删除目录

killall mysqld   #结束mysql进程

service mysqld start  #启动mysql

/etc/rc.d/init.d/mysqld status   #查看mysql状态

mysql_secure_installation  #重置Mysql数据库密码

#####################################################################################