第1章 yum是什么

YUM（Yellow dog Updater Modified）为多个Linux发行版的软件包管理器，例如Redhat RHEL,CentOS&Fedoro。

YUM主要用于自动安装、升级rpm软件包，它能自动查找并解决rpm包之间的依赖关系。

YUM自动下载rpm包并安装。类似某软件的一键安装。

1.1 yum源是什么？

要成功的使用YUM工具安装更新软件或系统，就需要有一个包含各种rpm软件包的repository（软件仓库），这个软件仓库我们习惯称为yum源。

网络上有大量的yum源，但由于受到网络环境的限制，导致软件安装耗时过长甚至失败令人难以忍受特别是当有大量服务器大量软件包需要安装时，缓慢的进度条因此我们在优化系统时，都会更换国内的源。

相比较而言，本地YUM源服务器最大优点是局域网的快速网络连接和稳定性。有了局域网中的YUM源服务器，即便在Internet连接中断的情况下，也不会影响其他YUM客户端的软件安装和升级。

1.2 yum工作原理

1.2.1 yum配置文件

[[email protected]_bak]# cat /etc/yum.conf

[main]定义了全局配置选项

cachedir=/var/cache/yum/$basearch/$releaseveryum缓存的目录,存储下载的rpm包和数据库

keepcache=0 是否保留安装包0为不保留,1为保留

debuglevel=2 debug信息输出等级,默认为2,范围0-10

logfile=/var/log/yum.log日志文件位置

exactarch=1 update的参数,相当于upgrade,允许更新旧的rpm包

obsoletes=1

有1和0两个选择,分别代表是否进行gpg(GNUPrivate Guard)校验,以确定rpm包的来源都是有效和安全的.这个选项如果设置在[main]部分,则对每个repository都有效.默认值 0

gpgcheck=1

plugins=1 是否启用插件,1表示允许,0不允许

installonly_limit=5

bugtracker_url=http://bugs.centos.org/set_project.php?project_id=19&ref=http://bugs.centos.org/bug_report_page.php?category=yum

distroverpkg=centos-release 指定一个软件包

# This is the default, if you make this biggeryum won‘t see if the metadata

# is neweron the remote and so you‘ll "gain" the bandwidth of not having to

# downloadthe new metadata and "pay" for it by yum not having correct

#information.

# It is esp. important, to have correctmetadata, for distributions like

# Fedorawhich don‘t keep old packages around. If you don‘t like this checking

#interupting your command line usage, it‘s much better to have something

# manuallycheck the metadata once an hour (yum-updatesd will do this).

#metadata_expire=90m

# PUT YOURREPOS HERE OR IN separate files named file.repo

# in/etc/yum.repos.d

1.2.2 yum命令用法

1.2.3 查看rpm帮助

[[email protected]~]# man rpm

RPM(8) RPM(8)

NAME

rpm - RPM Package Manager

SYNOPSIS

QUERYING AND VERIFYING PACKAGES:

rpm {-q|--query} [select-options][query-options]

rpm {-V|--verify} [select-options][verify-options]

rpm --import PUBKEY ...

rpm {-K|--checksig} [--nosignature][--nodigest]

PACKAGE_FILE ...

INSTALLING, UPGRADING, AND REMOVINGPACKAGES:

rpm {-i|--install} [install-options]PACKAGE_FILE ...

rpm {-U|--upgrade} [install-options]PACKAGE_FILE ...

rpm {-F|--freshen} [install-options]PACKAGE_FILE ...

rpm {-e|--erase} [--allmatches][--nodeps] [--noscripts]

[--notriggers] [--test] PACKAGE_NAME...

MISCELLANEOUS:

rpm {--initdb|--rebuilddb}

rpm {--addsign|--resign} PACKAGE_FILE...

rpm {--querytags|--showrc}

1.2.4 查看rpm包信息

[[email protected]/server/scripts]# rpm -qpinginx-1.6.3-1.x86_64.rpm

Name : nginx Relocations: /

Version : 1.6.3 Vendor: [email protected]

Release : 1 Build Date: 2016年06月26日星期日 10时57分54秒

InstallDate: (not installed) BuildHost: m01

Group : default Source RPM:nginx-1.6.3-1.src.rpm

Size : 5252902 License: unknown

Signature : (none)

Packager : <[email protected]>

URL : http://example.com/no-uri-given

Summary : no description given

Description:

nodescription given

1.2.5 查看rpm包内容

[[email protected]~]# rpm -qvl nginx-1.6.3-1.x86_64.rpm

packagenginx-1.6.3-1.x86_64.rpm is not installed

1.2.6 查看rpm包的依赖

[[email protected]~]# rpm -qpR nginx-1.6.3-1.x86_64.rpm

pcre-devel

openssl-devel

/bin/sh

rpmlib(PayloadFilesHavePrefix)<= 4.0-1

rpmlib(CompressedFileNames)<= 3.0.4-1

1.2.7 多个rpm包互相依赖强制安装

rpm -Uvh--aid *.rpm

或

rpm –ivh *.rpm--nodeps --force

1.2.8 查看rpm自带脚本

[[email protected]~]# rpm -qp --scriptsnginx-1.6.3-1.x86_64.rpm

postinstallscriptlet (using /bin/sh):

#!/bin/bash

useraddnginx -M -s /sbin/nologin

ln -s/application/nginx-1.6.3/ /application/nginx

cp/application/nginx/sbin/* /usr/local/sbin/

1.3 安装createrepo软件

1.3.1 方法1

上传createrepo.tar.gz软件安装

[[email protected]~]# cd /tmp/

[[email protected]]# ls

yum.log

[[email protected]]# rz -E

rz waitingto receive.

[[email protected]]# tar xf

createrepo.tar.gz .ICE-unix/ yum.log

[[email protected]]# tar xf createrepo.tar.gz

[[email protected]]# ls

createrepo-0.9.9-24.el6.noarch.rpm deltarpm-3.5-0.5.20090913git.el6.x86_64.rpm yum.log

createrepo.tar.gz python-deltarpm-3.5-0.5.20090913git.el6.x86_64.rpm

[[email protected]]# rpm -ivh *.rpm

Preparing... ########################################### [100%]

1:deltarpm ########################################### [ 33%]

2:python-deltarpm ########################################### [ 67%]

3:createrepo ########################################### [100%]

1.3.2 方法2

[[email protected]~]# yum -y install createrepo

已加载插件：fastestmirror, security

设置安装进程

Loadingmirror speeds from cached hostfile

epel/metalink | 5.5 kB 00:00

* base: mirrors.yun-idc.com

* epel: mirrors.neusoft.edu.cn

* extras: mirrors.yun-idc.com

* updates: mirrors.tuna.tsinghua.edu.cn

base | 3.7 kB 00:00

epel | 4.3 kB 00:00

epel/primary_db | 5.8 MB 00:25

extras | 3.4 kB 00:00

updates |3.4 kB 00:00

解决依赖关系

--> 执行事务检查

--->Package createrepo.noarch 0:0.9.9-24.el6 will be 安装

--> 处理依赖关系 python-deltarpm，它被软件包 createrepo-0.9.9-24.el6.noarch 需要

--> 执行事务检查

---> Packagepython-deltarpm.x86_64 0:3.5-0.5.20090913git.el6 will be 安装

--> 处理依赖关系 deltarpm =3.5-0.5.20090913git.el6，它被软件包python-deltarpm-3.5-0.5.20090913git.el6.x86_64 需要

--> 执行事务检查

--->Package deltarpm.x86_64 0:3.5-0.5.20090913git.el6 will be 安装

--> 完成依赖关系计算

依赖关系解决

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

软件包架构版本仓库大小

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

正在安装:

createrepo noarch 0.9.9-24.el6 base 96 k

为依赖而安装:

deltarpm x86_64 3.5-0.5.20090913git.el6 base 71 k

python-deltarpm x86_64 3.5-0.5.20090913git.el6 base 27 k

事务概要

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

Install 3 Package(s)

总下载量：194 k

Installedsize: 520 k

下载软件包：

(1/3):createrepo-0.9.9-24.el6.noarch.rpm | 96 kB 00:00

(2/3):deltarpm-3.5-0.5.20090913git.el6.x86_64.rpm | 71 kB 00:00

(3/3):python-deltarpm-3.5-0.5.20090913git.el6.x86_64.rpm | 27 kB 00:00

--------------------------------------------------------------------------------------------------------------------

总计 422 kB/s | 194 kB 00:00

运行 rpm_check_debug

执行事务测试

事务测试成功

执行事务

Warning:RPMDB altered outside of yum.

正在安装 :deltarpm-3.5-0.5.20090913git.el6.x86_64 1/3

正在安装 :python-deltarpm-3.5-0.5.20090913git.el6.x86_64 2/3

正在安装 :createrepo-0.9.9-24.el6.noarch 3/3

Verifying : python-deltarpm-3.5-0.5.20090913git.el6.x86_64 1/3

Verifying : deltarpm-3.5-0.5.20090913git.el6.x86_64 2/3

Verifying : createrepo-0.9.9-24.el6.noarch 3/3

已安装:

createrepo.noarch 0:0.9.9-24.el6

作为依赖被安装:

deltarpm.x86_640:3.5-0.5.20090913git.el6 python-deltarpm.x86_64 0:3.5-0.5.20090913git.el6

完毕！

1.4 创建yum仓库目录

1.4.1.1 执行命令

mkdir -p /application/yum/centos6/x86_64/

cd /application/yum/centos6/x86_64/

1.4.1.2 执行结果

[[email protected]~]# mkdir -p /application/yum/centos6/x86_64/

[[email protected]~]# cd /application/yum/centos6/x86_64/

[[email protected]/application/yum/centos6/x86_64]# cp/root/*.rpm .

[[email protected] /application/yum/centos6/x86_64]#ls -l

总用量 7100

-rw-r--r--1 root root 29456 6月 26 14:22 keyutils-libs-devel-1.4-5.el6.x86_64.rpm

-rw-r--r--1 root root 515904 6月 26 14:22 krb5-devel-1.10.3-57.el6.x86_64.rpm

-rw-r--r--1 root root 788956 6月 26 14:22 krb5-libs-1.10.3-57.el6.x86_64.rpm

-rw-r--r--1 root root 33424 6月 26 14:22 libcom_err-devel-1.41.12-22.el6.x86_64.rpm

-rw-r--r--1 root root 111508 6月 26 14:22 libselinux-2.0.94-7.el6.x86_64.rpm

-rw-r--r--1 root root 140160 6月 26 14:22 libselinux-devel-2.0.94-7.el6.x86_64.rpm

-rw-r--r--1 root root 84072 6月 26 14:22 libselinux-utils-2.0.94-7.el6.x86_64.rpm

-rw-r--r--1 root root 65484 6月 26 14:22 libsepol-devel-2.0.41-4.el6.x86_64.rpm

-rw-r--r--1 root root 2273453 6月 26 14:22 nginx-1.6.3-1.x86_64.rpm

-rw-r--r--1 root root 1597532 6月 26 14:22 openssl-1.0.1e-48.el6_8.1.x86_64.rpm

-rw-r--r--1 root root 1226260 6月 26 14:22openssl-devel-1.0.1e-48.el6_8.1.x86_64.rpm

-rw-r--r--1 root root 327960 6月 26 14:22 pcre-devel-7.8-7.el6.x86_64.rpm

-rw-r--r--1 root root 44984 6月 26 14:22 zlib-devel-1.2.3-29.el6.x86_64.rpm

1.4.2 单独指定软件包下载

yumdownloader pcre-devel

1.5 初始化repodata索引文件

1.5.1 第一次初始化

[[email protected]/application/yum/centos6/x86_64]# createrepo-pdo /application/yum/centos6/x86_64/ /application/yum/centos6/x86_64/

Spawningworker 0 with 13 pkgs

WorkersFinished

Gatheringworker results

SavingPrimary metadata

Saving filelists metadata

Savingother metadata

Generatingsqlite DBs

Sqlite DBscomplete

[[email protected]/application/yum/centos6/x86_64]# ls -l

总用量 7104