Linux常用命令笔记---YUM

 软件包名称-软件包版本-软件包修订次数(3.el).适用的硬件平台.扩展名

 

[root@szm bash]# yum -h

Loaded plugins: fastestmirror, priorities, refresh-packagekit

Usage: yum [options] COMMAND

 

List of Commands:

 

check          Check for problems in the rpmdb

check-update   Check for available package updates

clean          Remove cached data

deplist        List a package's dependencies

distribution-synchronization Synchronize installed packages to the latest available versions

downgrade      downgrade a package---下载可用升级包

erase          Remove a package or packages from your system

groupinfo      Display details about a package group

groupinstall   Install the packages in a group on your system

grouplist      List available package groups

groupremove    Remove the packages in a group from your system

help           Display a helpful usage message

history        Display, or use, the transaction history

info           Display details about a package or group of packages

install        Install a package or packages on your system

list           List a package or groups of packages

load-transaction load a saved transaction from filename

makecache      Generate the metadata cache

provides       Find what package provides the given value--从特别的文件搜索软件包

reinstall      reinstall a package

repolist       Display the configured software repositories----查看软件仓库信息

resolvedep     Determine which package provides the given dependency--查询软件包依赖

search         Search package details for the given string

shell          Run an interactive yum shell

update         Update a package or packages on your system

upgrade        Update packages taking obsoletes into account

version        Display a version for the machine and/or available repos.

 

 

Options:

  -h, --help            show this help message and exit

  -t, --tolerant        be tolerant of errors

  -C, --cacheonly       run entirely from system cache, don't update cache

  -c [config file], --config=[config file]

                        config file location

  -R [minutes], --randomwait=[minutes]

                        maximum command wait time

  -d [debug level], --debuglevel=[debug level]

                        debugging output level

  --showduplicates      show duplicates, in repos, in list/search commands

  -e [error level], --errorlevel=[error level]

                        error output level

  --rpmverbosity=[debug level name]

                        debugging output level for rpm

  -q, --quiet           quiet operation

  -v, --verbose         verbose operation

  -y, --assumeyes       answer yes for all questions

  --version             show Yum version and exit

  --installroot=[path]  set install root----设置指定安装目录

  --enablerepo=[repo]   enable one or more repositories (wildcards allowed)

  --disablerepo=[repo]  disable one or more repositories (wildcards allowed)

  -x [package], --exclude=[package]

                        exclude package(s) by name or glob

  --disableexcludes=[repo]

                        disable exclude from main, for a repo or for

                        everything

  --obsoletes           enable obsoletes processing during updates

  --noplugins           disable Yum plugins

  --nogpgcheck          disable gpg signature checking

  --disableplugin=[plugin]

                        disable plugins by name

  --enableplugin=[plugin]

                        enable plugins by name

  --skip-broken         skip packages with depsolving problems

  --color=COLOR         control whether color is used

  --releasever=RELEASEVER

                        set value of $releasever in yum config and repo files

  --setopt=SETOPTS      set arbitrary config and repo options

 

  Plugin Options:

    --samearch-priorities

                        Priority-exclude packages based on name + arch

-localinstall安装本地rpm文件，解决依赖问题

[root@szm bash]# yum search zsh

Loaded plugins: fastestmirror, priorities, refresh-packagekit

Loading mirror speeds from cached hostfile

 * base: centos.ustc.edu.cn

 * epel: mirrors.ustc.edu.cn

 * extras: centos.ustc.edu.cn

 * remi: rpms.famillecollet.com

 * rpmforge: mirror.oscc.org.my

 * updates: mirror01.idc.hinet.net

epel/pkgtags                                                                             |  325 B     00:00     

=============================================== N/S Matched: zsh ===============================================

autojump-zsh.noarch : Autojump for zsh

gromacs-zsh.noarch : GROMACS zsh support

python-twisted-core-zsh.i686 : Tab completion for Zsh and Twisted Core

zsh-html.i686 : Zsh shell manual in html format

zsh.i686 : A powerful interactive shell

 

  Name and summary matches only, use "search all" for everything.

 

[root@szm bash]# yum info zsh-html

Loaded plugins: fastestmirror, priorities, refresh-packagekit

Loading mirror speeds from cached hostfile

 * base: centos.ustc.edu.cn

 * epel: mirrors.ustc.edu.cn

 * extras: centos.ustc.edu.cn

 * remi: rpms.famillecollet.com

 * rpmforge: mirror.oscc.org.my

 * updates: mirror01.idc.hinet.net

Available Packages

Name        : zsh-html

Arch        : i686

Version     : 4.3.10

Release     : 5.el6

Size        : 454 k

Repo        : base

Summary     : Zsh shell manual in html format

URL         : http://zsh.sunsite.dk/

License     : BSD

Description : The zsh shell is a command interpreter usable as an interactive login

            : shell and as a shell script command processor.  Zsh resembles the ksh

            : shell (the Korn shell), but includes many enhancements.  Zsh supports

            : command line editing, built-in spelling correction, programmable

            : command completion, shell functions (with autoloading), a history

            : mechanism, and more.

            : 

            : This package contains the Zsh manual in html format.

 

[root@szm bash]# yum grouplist

 

查询软件包安装了哪些文件：
[root@szm bash]# yum whatprovides /bin/ls

Loaded plugins: fastestmirror, priorities, refresh-packagekit

Loading mirror speeds from cached hostfile

 * base: centos.ustc.edu.cn

 * epel: mirrors.ustc.edu.cn

 * extras: centos.ustc.edu.cn

 * remi: rpms.famillecollet.com

 * rpmforge: mirror.oscc.org.my

 * updates: mirror01.idc.hinet.net

coreutils-8.4-19.el6.i686 : A set of basic GNU tools commonly used in shell scripts

Repo        : base

Matched from:

Filename    : /bin/ls

 

 

 

coreutils-8.4-19.el6.i686 : A set of basic GNU tools commonly used in shell scripts

Repo        : installed

Matched from:

Other       : Provides-match: /bin/ls

 

 

[root@szm bash]# rpm --help

Usage: rpm [OPTION...]

  --quiet

 

Query/Verify package selection options:

  -a, --all                        query/verify all packages

  -f, --file                       query/verify package(s) owning file

  -g, --group                      query/verify package(s) in group

  -p, --package                    query/verify a package file--查询未安装rpm文件

  -W, --ftswalk                    query/verify package(s) from TOP file tree walk

  --pkgid                          query/verify package(s) with package identifier

  --hdrid                          query/verify package(s) with header identifier

  --fileid                         query/verify package(s) with file identifier

  --specfile                       query a spec file

  --triggeredby                    query the package(s) triggered by the package

  --whatrequires                   query/verify the package(s) which require a dependency

  --whatprovides                   query/verify the package(s) which provide a dependency

  --nomanifest                     do not process non-package files as manifests

 

Query options (with -q or --query):

  -c, --configfiles                list all configuration files

  -d, --docfiles                   list all documentation files

  --dump                           dump basic file information

  -l, --list                       list files in package

  --queryformat=QUERYFORMAT        use the following query format

  -s, --state                      display the states of the listed files

 

Verify options (with -V or --verify):

  --nofiledigest                   don't verify digest of files

  --nomd5                          don't verify digest of files

  --nofiles                        don't verify files in package

  --nodeps                         don't verify package dependencies

  --noscript                       don't execute verify script(s)

 

File tree walk options (with --ftswalk):

  --comfollow                      follow command line symlinks

  --logical                        logical walk

  --nochdir                        don't change directories

  --nostat                         don't get stat info

  --physical                       physical walk

  --seedot                         return dot and dot-dot

  --xdev                           don't cross devices

  --whiteout                       return whiteout information

 

Signature options:

  --addsign                        sign package(s) (identical to --resign)

  -K, --checksig                   verify package signature(s)

  --delsign                        delete package signatures

  --import                         import an armored public key

  --resign                         sign package(s) (identical to --addsign)

  --nodigest                       don't verify package digest(s)

  --nosignature                    don't verify package signature(s)

 

Database options:

  --initdb                         initialize database

  --rebuilddb                      rebuild database inverted lists from installed package headers

 

Install/Upgrade/Erase options:

  --aid                            add suggested packages to transaction

  --allfiles                       install all files, even configurations which might otherwise be skipped

  --allmatches                     remove all packages which match <package> (normally an error is generated

                                   if <package> specified multiple packages)

  --badreloc                       relocate files in non-relocatable package

  -e, --erase=<package>+           erase (uninstall) package

  --excludedocs                    do not install documentation

  --excludepath=<path>             skip files with leading component <path> 

  --fileconflicts                  detect file conflicts between packages

  --force                          short hand for --replacepkgs --replacefiles强制安装

  -F, --freshen=<packagefile>+     upgrade package(s) if already installed

  -h, --hash                       print hash marks as package installs (good with -v)

  --ignorearch                     don't verify package architecture

  --ignoreos                       don't verify package operating system

  --ignoresize                     don't check disk space before installing

  -i, --install                    install package(s)

  --justdb                         update the database, but do not modify the filesystem

  --nodeps                         do not verify package dependencies

  --nofiledigest                   don't verify digest of files

  --nomd5                          don't verify digest of files (obsolete)

  --nocontexts                     don't install file security contexts

  --noorder                        do not reorder package installation to satisfy dependencies

  --nosuggest                      do not suggest missing dependency resolution(s)

  --noscripts                      do not execute package scriptlet(s)

  --notriggers                     do not execute any scriptlet(s) triggered by this package

  --oldpackage                     upgrade to an old version of the package (--force on upgrades does this(安装旧版本软件)

                                   automatically)

  --percent                        print percentages as package installs

  --prefix=<dir>                   relocate the package to <dir>, if relocatable

  --relocate=<old>=<new>           relocate files from path <old> to <new>

  --replacefiles                   ignore file conflicts between packages

  --replacepkgs                    reinstall if the package is already present

  --test                           don't install, but tell if it would work or not

  -U, --upgrade=<packagefile>+     upgrade package(s)

 

Common options for all rpm modes and executables:

  -D, --define='MACRO EXPR'        define MACRO with value EXPR

  -E, --eval='EXPR'                print macro expansion of EXPR

  --macros=<FILE:...>              read <FILE:...> instead of default file(s)

  --nodigest                       don't verify package digest(s)

  --nosignature                    don't verify package signature(s)

  --rcfile=<FILE:...>              read <FILE:...> instead of default file(s)

  -r, --root=ROOT                  use ROOT as top level directory (default: "/")

  --querytags                      display known query tags

  --showrc                         display final rpmrc and macro configuration

  --quiet                          provide less detailed output

  -v, --verbose                    provide more detailed output

  --version                        print the version of rpm being used

 

Options implemented via popt alias/exec:

  --scripts                        list install/erase scriptlets from package(s)

  --setperms                       set permissions of files in a package

  --setugids                       set user/group ownership of files in a package

  --conflicts                      list capabilities this package conflicts with

  --obsoletes                      list other packages removed by installing this package

  --provides                       list capabilities that this package provides

  --requires   (-R)                list capabilities required by package(s)

  --info                           list descriptive information from package(s)

  --changelog                      list change logs for this package

  --xml                            list metadata in xml

  --triggers                       list trigger scriptlets from package(s)

  --last                           list package(s) by install time, most recent first

  --dupes                          list duplicated packages

  --filesbypkg                     list all files from each package

  --fileclass                      list file names with classes

  --filecolor                      list file names with colors

  --fscontext                      list file names with security context from file system

  --fileprovide                    list file names with provides

  --filerequire                    list file names with requires

  --filecaps                       list file names with POSIX1.e capabilities

 

Help options:

  -?, --help                       Show this help message

  --usage                          Display brief usage message

 

rpm数据库：

[root@szm bash]# cat /var/lib/rpm/

Basenames       __db.003        Group           Packages        Requirename     Sigmd5

Conflictname    __db.004        Installtid      Providename     Requireversion  Triggername

__db.001        Dirnames        Name            Provideversion  .rpm.lock       

__db.002        Filedigests     Obsoletename    Pubkeys         Sha1header 

 

 

查询所有配置文件

[root@szm bash]# rpm -qc bind

 

查询所有帮助文件：

[root@szm bash]# rpm -qd  bind

 

文件属于哪个软件：

[root@szm bash]# rpm -qf /etc/passwd

setup-2.8.14-20.el6.noarch

 

依赖关系：

[root@szm bash]# rpm -qR bind

 

依赖关系和没安装的包：

[root@szm bash]# rpm -qRp bind

 

查询软件包安装文件：

[root@szm bash]# rpm -ql bind

 

rpm验证数字签名：

[root@szm bash]# rpm -Va

....L....  c /etc/dracut.conf

....L....  c /etc/pulse/default.pa

S.5....T.  c /etc/rsyslog.conf

S.5....T.  c /etc/dumpdates

S.5....T.  c /etc/pam_ldap.conf

S.5....T.  c /etc/yp.conf

S.5....T.  c /etc/sudoers

.......T.  c /etc/dnsmasq.conf

S.5....T.  c /etc/vsftpd/vsftpd.conf

S.5....T.  c /etc/openldap/ldap.conf

..5....T.    /usr/share/ibus-table/tables/compose.db

..5....T.    /usr/share/ibus-table/tables/latex.db

S.5....T.  c /etc/updatedb.conf

S.5....T.  c /var/lib/nfs/etab

.M.......  c /etc/cups/subscriptions.conf

.M....G..    /var/log/gdm

.M.......    /var/run/gdm

missing     /var/run/gdm/greeter

....L....  c /etc/pam.d/fingerprint-auth

....L....  c /etc/pam.d/password-auth

....L....  c /etc/pam.d/smartcard-auth

....L....  c /etc/pam.d/system-auth

prelink: /usr/lib/libunistring.so.0.1.2: at least one of file's dependencies has changed since prelinking

S.?......    /usr/lib/libunistring.so.0.1.2

.......T.    /var/log/tomcat6/catalina.out

..5....T.  c /etc/inittab

..5....T.    /etc/ld.so.conf.d/kernel-2.6.32-71.el6.i686.conf

S.5......    /usr/libexec/perf.2.6.32-71.el6.i686

 

第一列：文件的属性  第二列：文件的类型  第三列：所检查的文件

S：文件大小或容量与原文件不同 M：文件的属性或权限与原文件不同 5：MD5的HASH值与原文件不同 D：设备文件的主次设备号与原文件不同 L：文件的链接路径与原文件不同 U：文件拥有人信息与原文件不同 G：文件拥有组成员与原文件不同 T：文件的创建时间与原文件

c：代表配置文件 d：代表文档 g：代表Ghost类型文件 l：代表版权类型文件 r：自述类型文件

 

数字签名：

 [root@szm Desktop]# ls /etc/pki/rpm-gpg/

RPM-GPG-KEY-CentOS-6        RPM-GPG-KEY-CentOS-Security-6  RPM-GPG-KEY-EPEL-6  RPM-GPG-KEY-rpmforge-dag

RPM-GPG-KEY-CentOS-Debug-6  RPM-GPG-KEY-CentOS-Testing-6   RPM-GPG-KEY-remi    RPM-GPG-KEY-rpmforge-fabian

 

[root@szm Desktop]# cat /etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6 

-----BEGIN PGP PUBLIC KEY BLOCK-----

Version: GnuPG v1.4.5 (GNU/Linux)

 

mQINBE4P06MBEACqn48FZgYkG2QrtUAVDV58H6LpDYEcTcv4CIFSkgs6dJ9TavCW

NyPBZRpM2R+Rg5eVqlborp7TmktBP/sSsxc8eJ+3P2aQWSWc5ol74Y0OznJUCrBr

bIdypJllsD9Fe+h7gLBXTh3vdBEWr2lR+xA+Oou8UlO2gFbVFQqMafUgU1s0vqaE

/hHH0TzwD0/tJ6eqIbHwVR/Bu6kHFK4PwePovhfvyYD9Y+C0vOYd5Ict2vbLHz1f

QBDZObv4M6KN3j7nzme47hKtdMd+LwFqxM5cXfM6b5doDulWPmuGV78VoX6OR7el

x1tlfpuiFeuXYnImm5nTawArcQ1UkXUSYcTUKShJebRDLR3BycxR39Q9jtbOQ29R

FumHginovEhdUcinRr22eRXgcmzpR00zFIWoFCwHh/OCtG14nFhefuZ8Z80qbVhW

2J9+/O4tksv9HtQBmQNOK5S8C4HNF2M8AfOWNTr8esFSDc0YA5/cxzdfOOtWam/w

lBpNcUUSSgddRsBwijPuWhVA3NmA/uQlJtAo4Ji5vo8cj5MTPG3+U+rfNqRxu1Yc

ioXRo4LzggPscaTZX6V24n0fzw0J2k7TT4sX007k+7YXwEMqmHpcMYbDNzdCzUer

Zilh5hihJwvGfdi234W3GofttoO+jaAZjic7a3p6cO1ICMgfVqrbZCUQVQARAQAB

tEZDZW50T1MtNiBLZXkgKENlbnRPUyA2IE9mZmljaWFsIFNpZ25pbmcgS2V5KSA8

Y2VudG9zLTYta2V5QGNlbnRvcy5vcmc+iQI8BBMBAgAmBQJOD9OjAhsDBQkSzAMA

BgsJCAcDAgQVAggDBBYCAwECHgECF4AACgkQCUb8osEFud6ajRAAnb6d+w6Y/v/d

MSy7UEy4rNquArix8xhqBwwjoGXpa37OqTvvcJrftZ1XgtzmTbkqXc+9EFch0C+w

ST10f+H0SPTUGuPwqLkg27snUkDAv1B8laub+l2L9erzCaRriH8MnFyxt5v1rqWA

mVlRymzgXK+EQDr+XOgMm1CvxVY3OwdjdoHNox4TdVQWlZl83xdLXBxkd5IRciNm

sg5fJAzAMeg8YsoDee3m4khg9gEm+/Rj5io8Gfk0nhQpgGGeS1HEXl5jzTb44zQW

qudkfcLEdUMOECbu7IC5Z1wrcj559qcp9C94IwQQO+LxLwg4kHffvZjCaOXDRiya

h8KGsEDuiqwjU9HgGq9fa0Ceo3OyUazUi+WnOxBLVIQ8cUZJJ2Ia5PDnEsz59kCp

JmBZaYPxUEteMtG3yDTa8c8jUnJtMPpkwpSkeMBeNr/rEH4YcBoxuFjppHzQpJ7G

hZRbOfY8w97TgJbfDElwTX0/xX9ypsmBezgGoOvOkzP9iCy9YUBc9q/SNnflRWPO

sMVrjec0vc6ffthu2xBdigBXhL7x2bphWzTXf2T067k+JOdoh5EGney6LhQzcp8m

YCTENStCR+L/5XwrvNgRBnoXe4e0ZHet1CcCuBCBvSmsPHp5ml21ahsephnHx+rl

JNGtzulnNP07RyfzQcpCNFH7W4lXzqM=

=jrWY

-----END PGP PUBLIC KEY BLOCK-----

 

安装证书：

[root@szm bash]# rpm --import ...

 

查询系统中已经安装了哪些数字证书：

[root@szm bash]# rpm -qa | grep -i GPG

pygpgme-0.1-18.20090824bzr68.el6.i686

gpg-pubkey-00f97f56-467e318a

gpgme-1.1.8-3.el6.i686

gpg-pubkey-0608b895-4bd22942

libgpg-error-1.7-4.el6.i686

gpg-pubkey-7fac5991-4615767f

gpg-pubkey-6b8d79e6-3f49313d

gpg-pubkey-c105b9de-4e0fd3a3

 

验证数字证书：

[root@szm Downloads]# rpm -K rpmforge-release-0.5.2-2.el6.rf.i686.rpm 

rpmforge-release-0.5.2-2.el6.rf.i686.rpm: (sha1) dsa sha1 md5 gpg OK

 

MD5校验：

[root@szm Downloads]# md5sum rpmforge-release-0.5.2-2.el6.rf.i686.rpm 

7cc287ef15afe2809d9d24b69ba4d434  rpmforge-release-0.5.2-2.el6.rf.i686.rpm

 

删除RPM包：

[root@szm Downloads]# rpm -e ...

 

YUM源配置：

 

 

Enable：0禁用，1启用  gpgcheck：0禁用，1启用 帮助文档：man yum.conf

 

查看系统所有可用的yum安装源：

[root@szm Downloads]# yum repolist all

Loaded plugins: fastestmirror, priorities, refresh-packagekit

Loading mirror speeds from cached hostfile

 * base: ftp.stu.edu.tw

 * epel: mirrors.ustc.edu.cn

 * extras: ftp.stu.edu.tw

 * remi: rpms.famillecollet.com

 * rpmforge: mirror.oscc.org.my

 * updates: mirror01.idc.hinet.net

http://dl.google.com/linux/rpm/stable/i386/repodata/repomd.xml: [Errno 14] PYCURL ERROR 7 - "Failed to connect to 2404:6800:4005:c00::5d: Network is unreachable"

Trying other mirror.

http://dl.google.com/linux/chrome/rpm/stable/i386/repodata/repomd.xml: [Errno 14] PYCURL ERROR 7 - "Failed to connect to 2404:6800:4005:c00::5d: Network is unreachable"

Trying other mirror.

http://dl.google.com/linux/rpm/stable/x86_64/repodata/repomd.xml: [Errno 14] PYCURL ERROR 7 - "Failed to connect to 2404:6800:4005:c00::5d: Network is unreachable"

Trying other mirror.

repo id                    repo name                                                              status

C6.0-base                  CentOS-6.0 - Base                                                      disabled

C6.0-centosplus            CentOS-6.0 - CentOSPlus                                                disabled

C6.0-contrib               CentOS-6.0 - Contrib                                                   disabled

C6.0-extras                CentOS-6.0 - Extras                                                    disabled

C6.0-updates               CentOS-6.0 - Updates                                                   disabled

C6.1-base                  CentOS-6.1 - Base                                                      disabled

C6.1-centosplus            CentOS-6.1 - CentOSPlus                                                disabled

C6.1-contrib               CentOS-6.1 - Contrib                                                   disabled

C6.1-extras                CentOS-6.1 - Extras                                                    disabled

C6.1-updates               CentOS-6.1 - Updates                                                   disabled

C6.2-base                  CentOS-6.2 - Base                                                      disabled

C6.2-centosplus            CentOS-6.2 - CentOSPlus                                                disabled

C6.2-contrib               CentOS-6.2 - Contrib                                                   disabled

C6.2-extras                CentOS-6.2 - Extras                                                    disabled

C6.2-updates               CentOS-6.2 - Updates                                                   disabled

C6.3-base                  CentOS-6.3 - Base                                                      disabled

C6.3-centosplus            CentOS-6.3 - CentOSPlus                                                disabled

C6.3-contrib               CentOS-6.3 - Contrib                                                   disabled

C6.3-extras                CentOS-6.3 - Extras                                                    disabled

C6.3-updates               CentOS-6.3 - Updates                                                   disabled

base                       CentOS-6 - Base                                                        enabled: 4,802

c6-media                   CentOS-6 - Media                                                       disabled

centosplus                 CentOS-6 - Plus                                                        disabled

contrib                    CentOS-6 - Contrib                                                     disabled

debug                      CentOS-6 - Debuginfo                                                   disabled

epel                       Extra Packages for Enterprise Linux 6 - i386                           enabled: 7,002

epel-debuginfo             Extra Packages for Enterprise Linux 6 - i386 - Debug                   disabled

epel-source                Extra Packages for Enterprise Linux 6 - i386 - Source                  disabled

epel-testing               Extra Packages for Enterprise Linux 6 - Testing - i386                 disabled

epel-testing-debuginfo     Extra Packages for Enterprise Linux 6 - Testing - i386 - Debug         disabled

epel-testing-source        Extra Packages for Enterprise Linux 6 - Testing - i386 - Source        disabled

extras                     CentOS-6 - Extras                                                      enabled:    12

google                     Google - i386                                                          enabled:     3

google-chrome              google-chrome                                                          enabled:     3

google64                   Google - x86_64                                                        enabled:     3

remi                       Les RPM de remi pour Enterprise Linux 6 - i386                         enabled:   953

remi-debuginfo             Les RPM de remi pour Enterprise Linux 6 - i386 - debuginfo             disabled

remi-test                  Les RPM de remi en test pour Enterprise Linux 6 - i386                 disabled

remi-test-debuginfo        Les RPM de remi en test pour Enterprise Linux 6 - i386 - debuginfo     disabled

rpmforge                   RHEL 6 - RPMforge.net - dag                                            enabled: 4,513

rpmforge-extras            RHEL 6 - RPMforge.net - extras                                         disabled

rpmforge-testing           RHEL 6 - RPMforge.net - testing                                        disabled

updates                    CentOS-6 - Updates                                                     enabled:   170

 

安装源软件列表缓存路径： [root@szm Downloads]# cat /var/cache/yum

 

清除缓存： [root@szm Downloads]# yum clean all