YUM源安装软件方式

• yum是什么？
  yum = Yellow dog Updater, Modified
  主要功能是更方便的添加/删除/更新RPM包.
  它能自动解决包的倚赖性问题.
  它能便于管理大量系统的更新问题
• yum特点
  可以同时配置多个资源库(Repository)
  简洁的配置文件(/etc/yum.conf，/etc/yum.repos.d 下的文件)
  自动解决增加或删除rpm包时遇到的倚赖性问题
  使用方便
  保持与RPM数据库的一致性
• yum工具安装

首先查看是否安装

rpm -qa  |grep yum

• Centos/RHEL
  #rpm -ivh yum-2.4.3-4.el4.centos.noarch.rpm

一般系统自带的yum源因没有买服务原因无法使用，需要清理原有的yum源文件后，重新定义：

定义yum源

cd /etc/yum.repos.d

[root@ocm1 yum.repos.d]# pwd

/etc/yum.repos.d

清空改目录下的所有的，以后缀为repo文件。

• 配置本地yum源语法格式如下：

将/etc/yum.repos.d 中的所有定义的Yum源配置文件删除。然后创建server.repo文件（扩展名一定是repo）内容如下：

[RHEL6]

name=local iso 

baseurl=file:///home/redhat-iso或者ftp://x.x.x.x、http://x.x.x.x

gpgcheck=0     --本地光盘或ISO安装，该配置最好改为0

enable=1

• 其中baseurl对 应的含义：

 baseurl:协议   路径

baseurl一般初学者老犯错误的地方，这里需要将ISO文件或光盘先mount到某个目录下：

如，虚拟机上挂载iso文件后，通过df -h 可得知，挂载到 /media/RHEL_5.5 i386 DVD目录下，而主目录名含空格，因此在baseurl=file:// /media/RHEL_5.5 i386 DVD 配置时，报错无法安装。

[root@ocm1 ~]# df -h

Filesystem            Size  Used Avail Use% Mounted on

/dev/sda3              29G  4.5G   24G  17% /

/dev/sda1              99M   12M   83M  12% /boot

tmpfs                1014M     0 1014M   0% /dev/shm

/dev/hdc              2.9G  2.9G     0 100% /media/RHEL_5.5 i386 DVD

需要如下两种方法来mount光盘或ISO文件:

[root@ocm1 ~]# mount /dev/hdc /mnt  

mount: block device /dev/hdc is write-protected, mounting read-only

[root@ocm1 ~]# df -h

Filesystem            Size  Used Avail Use% Mounted on

/dev/sda3              29G  4.5G   24G  17% /

/dev/sda1              99M   12M   83M  12% /boot

tmpfs                1014M     0 1014M   0% /dev/shm

/dev/hdc              2.9G  2.9G     0 100% /media/RHEL_5.5 i386 DVD

/dev/hdc              2.9G  2.9G     0 100% /mnt

[root@ocm1 ~]# cd /mnt/Server/

或者

[root@ocm1 ~]# mount /dev/cdrom /media/

mount: block device /dev/cdrom is write-protected, mounting read-only

[root@ocm1 ~]# df -h

Filesystem            Size  Used Avail Use% Mounted on

/dev/sda3              29G  4.5G   24G  17% /

/dev/sda1              99M   12M   83M  12% /boot

tmpfs                1014M     0 1014M   0% /dev/shm

df: `/media/RHEL_5.5 i386 DVD': No such file or directory

/dev/hdc              2.9G  2.9G     0 100% /media

[root@ocm1 ~]# cd /media/Server/

以上配置结束后，就可以使用yum了，如下所示（如下案例，先卸载ftp包再安装的）：

[root@ocm1 yum.repos.d]# yum install -y lftp*

Loaded plugins: rhnplugin, security

This system is not registered with RHN.

RHN support will be disabled.

ClusterStorage                                                                                                                           | 1.3 kB     00:00    

RHEL6                                                                                                                                    | 1.3 kB     00:00    

RHEL6/primary                                                                                                                            | 753 kB     00:00    

RHEL6                                                                                                                                                 2348/2348

iso                                                                                                                                      | 1.3 kB     00:00    

Setting up Install Process

Resolving Dependencies

--> Running transaction check

---> Package lftp.i386 0:3.7.11-4.el5 set to be updated

--> Finished Dependency Resolution

Dependencies Resolved

===========================================================================================

 Package                             Arch                                Version                                     Repository                            Size

===============================================================================================

Installing:

 lftp                                i386                                3.7.11-4.el5                                RHEL6                                929 k

Transaction Summary

===============================================================================================

Install       1 Package(s)

Upgrade       0 Package(s)

Total download size: 929 k

Downloading Packages:

Running rpm_check_debug

Running Transaction Test

Finished Transaction Test

Transaction Test Succeeded

Running Transaction

  Installing     : lftp                                                                                                                                     1/1

Installed:

  lftp.i386 0:3.7.11-4.el5                                                                                                                                     

Complete!

[root@ocm1 yum.repos.d]#