Yum Centos

yum - Yellowdog Updater Modified

yum is an interactive, rpm based, package manager. It can automatically perform system updates, including dependency analysis and obsolete processing based on "repository" metadata. It can also perform installation of new packages, removal of old packages and perform queries on the installed and/or available packages among many other commands/services (see below).

yum is similar to other high level package managers like apt-get and smart.

While there are some graphical interfaces directly to the yum code, more recent graphical interface development is happening with PackageKit and the gnome-packagekit application.

Additional packages

To install rpmforge extras it's necessary to install the rpmforge-release package by hand. The example below is for Centos 6. See http://wiki.centos.org/AdditionalResources/Repositories/RPMForge or http://pkgs.repoforge.org/rpmforge-release/ for your version.

rpm --import http://apt.sw.be/RPM-GPG-KEY.dag.txt
wget http://packages.sw.be/rpmforge-release/rpmforge-release-0.5.2-2.el6.rf.x86_64.rpm
rpm -K rpmforge-release-0.5.2-2.el6.rf.*.rpm
rpm -i rpmforge-release-0.5.2-2.el6.rf.*.rpm

Installing packages

[root@centos1 ~]# <input>yum -y install atftp-server</input>
<notice>...OMITTED OUTPUT...</notice>
---> Package atftp-server.x86_64 0:0.7-6.el6.rf will be installed
Installed:
  atftp-server.x86_64 0:0.7-6.el6.rf

Listing installed packages

To list installed packages it is necessary to use rpm

[root@centos1 ~]# <input>rpm -qa</input>
iwl100-firmware-39.31.5.1-1.el6.noarch
hwdata-0.233-7.6.el6.noarch
aic94xx-firmware-30-2.el6.noarch
rpcbind-0.2.0-8.el6.x86_64
<notice>...OMITTED OUTPUT...</notice>

Finding packages

By known filename

using a glob */FILENAME will instruct yum to search for a file in a package

For example remembering that the configuration file for a dhcp server is called dhcpd.conf - you search for the package name with the following command, and find the package is called dhcp or more specific dhcp-4.1.1-25.P1.el6.x86_64

[root@centos1 ~]# <input>yum provides */dhcpd.conf</input>
Loaded plugins: fastestmirror, security
<notice>...OMITTED OUTPUT...</notice>
12:dhcp-4.1.1-25.P1.el6.x86_64 : Dynamic host configuration protocol software
Repo        : base
Matched from:
Filename    : /etc/dhcp/dhcpd.conf

By known function or words

It is possible to search all available packages for a text string. For example searching for a specific tftp server

[root@centos1 ~]# <input>yum search all "tftp"</input>
================================= Matched: tftp =================================
atftp.x86_64 : Advanced Trivial File Transfer Protocol (TFTP) client
atftp-server.x86_64 : Advanced Trivial File Transfer Protocol (TFTP) server
perl-Net-TFTP.noarch : TFTP Client class
<notice>...OUTPUT OMITTED...</output>

Obtaining information about a package

[root@centos1 ~]# <input>yum info atftp</input>
Available Packages
Name        : atftp
<notice>...OUTPUT OMITTED...</notice>
Description : atftp is an advanced client implementation of the TFTP
            : protocol that implements RFCs 1350, 2090, 2347, 2348, and 2349.
            : The server is multi-threaded and the client presents a friendly
            : interface using libreadline. The current server implementation
            : lacks IPv6 support.

To which package does a file belong

What package does this file belong to /etc/sestatus.conf.

[root@centos1 etc]# <input>rpm -qf /etc/sestatus.conf<input>
policycoreutils-2.0.83-19.21.el6_2.x86_64
[root@centos1 etc]# <input>yum info policycoreutils-2.0.83-19.21.el6_2.x86_64</input>
Description : Security-enhanced Linux is a feature of the Linux® kernel and a number
            : of utilities with enhanced security functionality designed to add
<notice>...OUTPUT OMITTED...</notice>

Listing files in a package

To see the files in a installed package you could use

[root@centos1 bin]# <input>rpm -ql  mpitests-openmpi-psm</input>
/usr/lib64/openmpi-psm/bin/mpitests-IMB-EXT
/usr/lib64/openmpi-psm/bin/mpitests-IMB-IO
<notice>...OUTPUT OMITTED...</notice>

Removing installed packages

[root@centos1 ~]# <input>yum remove rpmforge-release</input>
---> Package rpmforge-release.i686 0:0.5.2-2.el6.rf will be erased
<notice>...OUTPUT OMITTED...</notice>
Removed:
  rpmforge-release.i686 0:0.5.2-2.el6.rf
Complete!

Listing available repos

[root@centos1 ~]# <input>yum repolist</input>
repo id                           repo name                                            status
base                              CentOS-6 - Base                                      6.294
extras                            CentOS-6 - Extras                                        4
rpmforge                          RHEL 6 - RPMforge.net - dag                          4.309
updates                           CentOS-6 - Updates                                     784

Working with groups

Groups are packages that belong together and can be installed or removed together.

Searching for a group

[root@centos1 ~]# <input>yum grouplist | grep -i nfs</input>
   NFS file server

==Updating

listing packages in a group

[root@centos1 ~]# <input>yum groupinfo "NFS file server"</input>
Group: NFS file server
 Description: NFS file server.
 Mandatory Packages:
   nfs-utils
   nfs4-acl-tools

Installing or removing a group

[root@centos1 ~]# <input>yum groupinstall "NFS file server"</input>
<notice>...OUTPUT OMITTED...</notice>
[root@centos1 ~]# <input>yum groupremove "NFS file server"</input>
<notice>...OUTPUT OMITTED...</notice>

Updating packages

[root@centos1 ~]# <input>yum update</input>
Loaded plugins: fastestmirror, security
Loading mirror speeds from cached hostfile
 * base: centos.intergenia.de
 * extras: centos.intergenia.de
 * rpmforge: ftp-stud.fht-esslingen.de
 * updates: centos.intergenia.de
Setting up Update Process
No Packages marked for Update