YUM(全稱為Yellow dog Updater, Modified)是一個在RHEL系操作系統中的Shell前端軟件包管理器。基於RPM包管理，能夠從指定的服務器自動下載RPM包並且安裝，可以自動處理依賴性關系，並且一次安裝所有依賴的軟件包，無須頻繁地一次次下載、安裝。
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YUM軟件包倉庫配置：
YUM軟件包管理器針對軟件包的操作都要依賴yum的倉庫來實現。而yum倉庫的配置可以編輯yum的配置文件(/etc/yum.conf、/etc/yum.repos.d/*repo)來實現。 一般情況/etc/yum.conf下主要是yum的主配置文件，/etc/yum.repos.d/*.repo主要是各個軟件倉庫的配置文件。
/etc/yum.conf：
/etc/yum.repos.d/media.repo：
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YUM安裝、升級和刪除軟件包：
# yum {install | update | remove} PACKAGE_NAME ...
示例 1：
軟件包的安裝：
示例 2：
軟件包的升級：
備注：yum update 後面跟隨軟件包名，是只檢測指定的軟件的更新
備注：yum update 命令檢測系統上所有已安裝軟件的更新
示例 3：
軟件包的刪除：
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YUM安裝、升級和刪除軟件包組：
# yum {groupinstall | groupupdate | groupremove} PACKAGEGROUP_NAME ...
// 安裝打印服務包組
// 包組名稱之間如果有空格，需要用引號引起來
[root@localhost ~]# yum groupinstall "Print Server"
// 升級打印服務包組
[root@localhost ~]# yum groupupdate "Print Server"
// 刪除打印服務包組
[root@localhost ~]# yum groupremove "Print Server"
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YUM其他的選項：
# yum list [all | installed | updates | available]
# yum grouplist
//列出所有的軟件包
//all可以省略
[root@localhost ~]# yum list all
[root@localhost ~]# yum list
//列出所有已安裝的軟件包
[root@localhost ~]# yum list installed
//列出所有需要更新的軟件包
[root@localhost ~]# yum list updates
//列出所有可用軟件包
[root@localhost ~]# yum list available
//列出所有包組
[root@localhost ~]# yum grouplist
# yum repolist [all | enabled | disabled]
//yum repolist默認顯示所有enabled軟件倉庫列表
[root@localhost ~]# yum repolist
//也可以手動指定enabled選項
[root@localhost ~]# yum repolist enabled
//列出所有disabled軟件倉庫列表
[root@localhost ~]# yum repolist disabled
//列出全部軟件倉庫列表
[root@localhost ~]# yum repolist all
# yum info [all | installed | updates | available | PACKAGE_NAME]
//顯示lftp軟件包信息
[root@localhost ~]# yum info lftp
Loaded plugins: fastestmirror, security
Loading mirror speeds from cached hostfile
* base: mirrors.hustunique.com
* extras: mirrors.hustunique.com
* updates: mirrors.hustunique.com
Installed Packages
Name : lftp
Arch : x86_64
Version : 4.0.9
Release : 1.el6_5.1
Size : 2.5 M
Repo : installed
From repo : updates
Summary : A sophisticated file transfer program
URL : http://lftp.yar.ru/
License : GPLv3+
Description : LFTP is a sophisticated ftp/http file transfer program. Like bash, it has job
: control and uses the readline library for input. It has bookmarks, built-in
: mirroring, and can transfer several files in parallel. It is designed with
: reliability in mind.
Available Packages
Name : lftp
Arch : i686
Version : 4.0.9
Release : 1.el6_5.1
Size : 735 k
Repo : updates
Summary : A sophisticated file transfer program
URL : http://lftp.yar.ru/
License : GPLv3+
Description : LFTP is a sophisticated ftp/http file transfer program. Like bash, it has job
: control and uses the readline library for input. It has bookmarks, built-in
: mirroring, and can transfer several files in parallel. It is designed with
: reliability in mind.
//其他選項可以顯示所有installed、updates、available和全部軟件包的信息
# yum groupinfo "PACKAGE_GROUP_NAME"
//顯示"Print Server"包組信息
[root@localhost ~]# yum groupinfo "Print Server"
Loaded plugins: fastestmirror, security
Setting up Group Process
Loading mirror speeds from cached hostfile
* base: ftp.stu.edu.tw
* extras: mirrors.hustunique.com
* updates: mirrors.hustunique.com
Group: Print Server
Description: Allows the system to act as a print server. //描述
Mandatory Packages: //必須安裝的包
cups
printer-filters
Default Packages: //默認安裝的包
foomatic-db-ppds
gutenprint
gutenprint-cups
hpijs
paps
# yum clean [ packages | metadata | expire-cache | rpmdb | plugins | all ]
# yum makecache
//清除軟件包緩沖
[root@localhost ~]# yum clean packages
Loaded plugins: fastestmirror, security
Cleaning repos: base extras updates
0 package files removed
//清除軟件包元數據緩沖
[root@localhost ~]# yum clean metadata
Loaded plugins: fastestmirror, security
Cleaning repos: base extras updates
13 metadata files removed
9 sqlite files removed
0 metadata files removed
//清除過期緩沖
[root@localhost ~]# yum clean expire-cache
Loaded plugins: fastestmirror, security
Cleaning repos: base extras updates
0 metadata files removed
//清除rpmdb數據庫
[root@localhost ~]# yum clean rpmdb
Loaded plugins: fastestmirror, security
Cleaning repos: base extras updates
4 rpmdb files removed
//清除補丁緩沖
[root@localhost ~]# yum clean plugins
Loaded plugins: fastestmirror, security
Cleaning repos: base extras updates
//清除所有緩沖
[root@localhost ~]# yum clean all
Loaded plugins: fastestmirror, security
Cleaning repos: base extras updates
Cleaning up Everything
//重建緩沖
[root@localhost ~]# yum makecache
Loaded plugins: fastestmirror, security
Loading mirror speeds from cached hostfile
* base: mirrors.163.com
* extras: mirrors.163.com
* updates: mirrors.163.com
base | 3.7 kB 00:00
base/group_gz | 220 kB 00:01
base/filelists_db | 5.9 MB 00:44
base/primary_db | 4.4 MB 00:29
base/other_db | 2.8 MB 00:25
extras | 3.4 kB 00:00
extras/filelists_db | 11 kB 00:00
extras/prestodelta | 907 B 00:00
extras/primary_db | 19 kB 00:00
extras/other_db | 5.8 kB 00:00
updates | 3.4 kB 00:00
updates/filelists_db | 1.5 MB 00:17
updates/prestodelta | 156 kB 00:01
updates/primary_db | 2.1 MB 00:19
updates/other_db | 244 kB 00:01
Metadata Cache Created
# yum check-update
# yum update [PACKAGE_NAME] ...
//檢測系統已安裝軟件包是否有更新
[root@localhost ~]# yum check-update
Loaded plugins: fastestmirror, security
Loading mirror speeds from cached hostfile
* base: mirrors.163.com
* extras: mirrors.163.com
* updates: mirrors.163.com
initscripts.x86_64 9.03.40-2.el6.CentOS.1 updates
libtiff.x86_64 3.9.4-10.el6_5 updates
phonon-backend-gstreamer.x86_64 1:4.6.2-28.el6_5 updates
postfix.x86_64 2:2.6.6-6.el6_5 updates
psmisc.x86_64 22.6-19.el6_5 updates
upstart.x86_64 0.6.5-13.el6_5.2 updates
//更新軟件包"postfix"
[root@localhost ~]# yum update postfix
//更新所有可更新的軟件包
[root@localhost ~]# yum update
# yum reinstall PACKAGE_NAME ...
//重新安裝軟件包
[root@localhost ~]# yum reinstall lftp
Loaded plugins: fastestmirror, security
Setting up Reinstall Process
Loading mirror speeds from cached hostfile
* base: mirrors.163.com
* extras: mirrors.163.com
* updates: mirrors.163.com
Resolving Dependencies
--> Running transaction check
---> Package lftp.x86_64 0:4.0.9-1.el6_5.1 will be reinstalled
--> Finished Dependency Resolution
# yum history
//查看此前yum操作歷史
[root@localhost ~]# yum history
Loaded plugins: fastestmirror, security
ID | Login user | Date and time | Action(s) | Altered
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11 | root <root> | 2014-03-01 23:31 | Install | 30
10 | root <root> | 2014-03-01 20:59 | Install | 1
9 | root <root> | 2014-03-01 20:50 | Erase | 1
8 | root <root> | 2014-03-01 20:47 | Install | 1
7 | root <root> | 2014-03-01 20:42 | Erase | 1 EE
6 | root <root> | 2014-03-01 20:41 | Update | 1 <
5 | root <root> | 2014-02-28 17:06 | Install | 1 ><
4 | root <root> | 2014-02-28 15:56 | Install | 8 >
3 | root <root> | 2014-02-28 13:09 | I, U | 115
2 | root <root> | 2014-02-17 17:20 | I, U | 54
1 | System <unset> | 2014-02-17 23:36 | Install | 621
history list
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