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1. Introduction

1.1. Purpose

This document presents basic concepts of software management on Fedora systems. It outlines the major functions of yum, the recommended software management tool for Fedora, and various graphical interfaces to yum.

1.2. Audience

This document is intended for Fedora users of all levels of experience.

1.3. Using This Document

This document is a reference for managing software with Fedora. You may wish to read some or all of the sections, depending upon your needs and level of experience. If you are a new user, start with:

These guides explain basic concepts of software management in Fedora, and introduce the various graphical interfaces for yum. Experienced Linux users should start with Section 4, “Managing Software with yum” .

Previous Versions of Fedora
This document describes the configuration of yum on current versions of Fedora. You must perform the additional step noted in Section 7.2, “Manually Authorizing Package Sources” to enable yum on earlier versions Fedora.
Avoid Logging in with the Root Account
You do not need to log in with the root account in order to manage your Fedora system. All of the commands shown in this tutorial that require root access will prompt you for the root password. The example terminal commands use su -c to provide this facility. Graphical applications that require root access will automatically prompt for the root password when launched.

Most of the examples in this document use the package tsclient, which is included with Fedora. The tsclient package provides an application for remote desktop access. The example commands for Fedora package groups use the MySQL Database group. To use the examples, substitute the name of the relevant package for tsclient.

Fedora includes a yum configuration that is suitable for independent systems with Internet access. You may use yum and related software on such systems without any additional configuration.

If your system is part of a managed network, consult your network administrators for advice. You may need to configure yum to use a network proxy server. Section 11, “Using yum with a Proxy Server” explains how to configure yum to use a proxy server. Administrators may also suggest or require that yum clients use specific package repositories. Refer to Section 7, “Configuring Access to Software Repositories” for instructions on how to configure access to repositories.

To improve performance and enable disconnected operations, activate the yum caches on your system. Refer to Section 10, “Working with yum Caching” for more information on the caching option.

1.4. Additional Resources

The yum utility has features and options not discussed in this document. Read the man pages for yum(8) and yum.conf(5) to learn more, using the following commands:

man yum

man yum.conf

Other useful yum resources on the Internet include:


Project Web site

http://linux.duke.edu/projects/yum/

Users mailing list

https://lists.dulug.duke.edu/mailman/listinfo/yum/

Development mailing list

https://lists.dulug.duke.edu/mailman/listinfo/yum-devel/

Check Bugzilla First
If you encounter a persistent error with a specific operation, visit https://bugzilla.redhat.com and review the bug reports for the package or packages involved. An error in a package may cause all yum operations that rely on that package to fail. Please file bug reports for Fedora packages, including yum, on this Bugzilla web site.
Previous Page - Table of Contents Table of Contents Next Page - 2. Software Management Concepts

2. Software Management Concepts

2.1. About Packages

Fedora software and documentation is supplied in the form of files called RPM packages. Each package is a compressed archive containing product information, program files, icons, documentation and management scripts. Management applications use these files to safely locate, install, update and remove software. For example, the Fedora installation process uses the packages supplied with Fedora to build or upgrade a system to your requirements.

Packages also include a digital signature to prove their source. Software management utilities verify this digital signature by using a GPG public key. The yum and rpm utilities share a common keyring that stores all of the public keys for approved package sources. The system administrator configures these approved package sources.

All Fedora Packages are Free and Open Source Software
All of the software provided by the Fedora Project is Free and open source software. You may download and install Fedora packages on as many systems as desired.

2.2. About Repositories

A repository is a prepared directory or Web site that contains software packages and index files. Software management utilities such as yum automatically locate and obtain the correct RPM packages from these repositories. This method frees you from having to manually find and install new applications or updates. You may use a single command to update all system software, or search for new software by specifying criteria.

A network of servers provide several repositories for each version of Fedora. The package management utilities in Fedora are already configured to use three of these repositories:

Base

The packages that make up a Fedora release, as it is on disc

Updates

Updated versions of packages that are provided in Base

Extras

Packages for a large selection of additional software

Fedora Development Repositories
Fedora also includes settings for several alternative repositories. These provide packages for various types of test system, and replace one or more of the standard repositories. Only enable support for one of the following repositories if you test or develop Fedora software: fedora-devel (Rawhide), fedora-extras-devel, and updates-testing.

Third-party software developers also provide repositories for their Fedora compatible packages. To learn how to configure your Fedora system to use third-party repositories, read Section 7, "Configuring Access to Software Repositories" .

You may also use the package groups provided by the Fedora repositories to manage related packages as sets. Some third-party repositories add packages to these groups, or provide their packages as additional groups.

Available Package Groups
To view a list of all of the available package groups for your Fedora system, run the command su -c 'yum grouplist'.

Use repositories to ensure that you always receive current versions of software. If several versions of the same package are available, your management utility automatically selects the latest version.

{Admon/caution | Manually Installing Software | Install software using manual methods only when you are confident there is no repository which can currently provide it. You may have to manage that software with manual methods, instead of with Fedora software management utilities.}}

The yum commands shown in this document use repositories as package sources. Refer to Section 8, "Installing Software from an Isolated Package" for details of using yum to install software from a package file.

2.3. About Dependencies

Some of the files installed on a Fedora distribution are libraries which may provide functions to multiple applications. When an application requires a specific library, the package which contains that library is a dependency. To properly install a package, Fedora must first satisfy its dependencies. The dependency information for a RPM package is stored within the RPM file.

The yum utility uses package dependency data to ensure that all of requirements for an application are met during installation. It automatically installs the packages for any dependencies not already present on your system. If a new application has requirements that conflict with existing software, yum aborts without making any changes to your system.

2.4. Understanding Package Names

Each package file has a long name that indicates several key pieces of information. For example, this is the full name of a tsclient package:

tsclient-0.132-6.i386.rpm

Management utilities commonly refer to packages with one of three formats:

  • Package name: tsclient
  • Package name with version and release numbers: tsclient-0.132-6
  • Package name with hardware architecture: tsclient.i386

For clarity, yum lists packages in the format name.architecture. Repositories also commonly store packages in separate directories by architecture. In each case, the hardware architecture specified for the package is the minimum type of machine required to use the package.

i386

Suitable for any current Intel-compatible computer

noarch

Compatible with all computer architectures

ppc

Suitable for PowerPC systems, such as Apple Power Macintosh

x86_64

Suitable for 64-bit Intel-compatible processors, such as Opterons

Some software may be optimized for particular types of Intel-compatible machine. Separate packages may be provided for i386, i586, i686 and x86_64 computers. A machine with at least an Intel Pentium, VIA C3 or compatible CPU may use i586 packages. Computers with an Intel Pentium Pro and above, or a current model of AMD chip, may use i686 packages.

Use the short name of the package for yum commands. This causes yum to automatically select the most recent package in the repositories that matches the hardware architecture of your computer.

Specify a package with other name formats to override the default behavior and force yum to use the package that matches that version or architecture. Only override yum when you know that the default package selection has a bug or other fault that makes it unsuitable for installation.

Package Names
You may use any of the following formats to specify a package in a yum operation: name, name.architecture, name-version, name-version-release, name-version-release.architecture, and epoch:name-version-release.architecture.
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3. Software Management Tools in Fedora

The yum command-line utility is a complete software management system. Fedora also includes two graphical applications for software management that use yum. The pup utility provides an interface for updating software, and the pirut application enables you to add or remove software.

Both graphical tools appear in the Applications desktop menu. To update your system with pup, select Applications → System Tools → Software Updater. To add or remove software with pirut, select Applications → Add/Remove Software.

Root Access Needed
When using pup or pirut you will be asked for the root password when starting these programs.

There is also puplet which automatically checks for, and alerts you to, updates for your system. It appears as an icon in the notification area when new updates are available. Click this icon to launch pup and update your system.

The rpm command-line utility has many functions for working with individual RPM packages. You may use it to manually install and remove packages from your system. If you install software with the rpm utility, you must manually check and install any dependencies. For this reason, pirut and yum are the recommended methods for installing software.

Current Package Versions
The pirut and yum utilities ensure that you have the most recent version of software packages. Other methods do not guarantee that the packages are current.

Updating Software With Pup

This section explains how to use the Pup graphical update program, and how Puplet works to provide notifications of available updates.

Update Notifications

Puplet works constantly in the background, checking for available software updates from the enabled repositories. When updates become available a package icon appears in the notification area, along with an alert which appears for a short time and reveals the number of updates available.

Once the notification tray icon is present, there are a number of possible actions it can perform:

  • Refresh will check for new updates
  • View Updates launches Pup and allows you to find more details about the packages to be updated, to de-select some updates, and to start the update process
  • Apply Updates
  • Quit closes Puplet until the next time the system starts

The Package Updater

This program features a scrollable text window under the heading Updates available. In this text window all of the available updates are listed, and all are selected by default. If you want to remove any of the packages queued for update, left click the ticked box next to the relevant package.

Some updates have a circular arrow icon next to them, indicating that these changes won't be applied until the next system reboot.

Further information about the updates can be found by selecting the desired package, then left clicking the Update Details text.

Once satisfied with the package selection left click the Apply Updates button. Pup checks for dependencies, ensuring that the updated packages will have everything required to function correctly. If dependencies are added a dialogue will be displayed informing you which new packages are set to be installed. Review this dialog and click Continue if it is OK.

The packages will then be downloaded and installed. If a reboot is needed for some of the changes to take place, you will be informed of this at the end of the updates.

Managing Software with Pirut

This section explains Pirut, Fedora's graphical package management program. It demonstrates the different search facilities within Pirut and how to install a package. The Banshee music management package is used as an example.

Browse Software

Start Pirut by selecting the Add/Remove Programs entry in the Applications menu, entering your root password when prompted.

The program starts in Browse view by default. This view organizes packages into related groups, displaying top level groups on the left and sub-categories on the right. When a tick is present next to a sub-category, it indicates applications from that group are installed.

To install Banshee, select the Sound and Video sub-category and press the Optional Packages button. Locate Banshee in the list and queue it for installation by ticking its box with a left-click. As many packages as desired can be queued for installation by ticking the appropriate boxes.

To add packages from other groups or sub-categories to the queue, browse to the desired group or sub-category and proceed as before. The Optional Packages button is only available when the desired sub-category is ticked. Ticking a previously un-ticked sub-category automatically queues for installation any packages required for that sub-category.

To install the queued packages press the Apply button.

Removing packages
Remove packages by un-ticking the appropriate boxes and pressing the Apply button.

Dependencies

After applying changes, Pirut prompts to confirm the packages you have selected. Proceed if the list is correct, otherwise cancel and refine the selection.

Dependencies
Dependenices are packages that are required by another package to function correctly.

Pirut now resolves any dependencies. A dialog informs you which dependencies have been found, and are automatically marked for installation. Confirm this list to proceed.

Dependencies can be removed
When a package is removed it is possible other packages may have relied on it to function correctly. If this is the case Pirut also removes these other applications. Check the dependency dialog and cancel if any of the packages marked for removal are still needed. This can be corrected by refining your package selection.

Search Software

When the desired application's name is known, the Search tab is more efficient.

Select the Search tab from the top of the window and enter Banshee into the search box. Press enter to begin the search. Results, including related packages, are shown in the box below. To find more information about a package before installation, highlight it with a left-click and press the Package Details text below.

To queue a package for installation or removal, toggle its box as appropriate. Once all the packages have been selected press Apply.

List Software

The list tab displays all available packages. Packages can be queued for installation or removal in the same manner as before. Once satisfied with the selections, press the Apply button to commit the changes.


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4. Managing Software with yum

Use the yum utility to modify the software on your system in four ways:

  • To install new software from package repositories
  • To install new software from an individual package file
  • To update existing software on your system
  • To remove unwanted software from your system
Installing Software from a Package File
The yum commands shown in this section use repositories as package sources. Refer to Section 8, “Installing Software from an Isolated Package” for details of using yum to install software from an individual package file.

To use yum, specify a function and one or more packages or package groups. Each section below gives some examples.

For each operation, yum downloads the latest package information from the configured repositories. If your system uses a slow network connection yum may require several seconds to download the repository indexes and the header files for each package.

The yum utility searches these data files to determine the best set of actions to produce the required result, and displays the transaction for you to approve. The transaction may include the installation, update, or removal of additional packages, in order to resolve software dependencies.

This is an example of the transaction for installing tsclient:

=============================================================================
Package                 Arch       Version          Repository        Size
=============================================================================
Installing:
tsclient                i386       0.132-6          base              247 k
Installing for dependencies:
rdesktop                i386       1.4.0-2          base              107 k

Transaction Summary
=============================================================================
Install      2 Package(s)
Update       0 Package(s)
Remove       0 Package(s)
Total download size: 355 k
Is this ok [y/N] :

Example 1. Format of yum Transaction Reports

Review the list of changes, and then press [y] to accept and begin the process. If you press [N] or [Enter] , yum does not download or change any packages.

Package Versions
The yum utility only displays and uses the newest version of each package, unless you specify an older version.

The yum utility also imports the repository public key if it is not already installed on the rpm keyring.

This is an example of the public key import:

warning: rpmts_HdrFromFdno: Header V3 DSA signature: NOKEY, key ID 4f2a6fd2
public key not available for tsclient-0.132-6.i386.rpm
Retrieving GPG key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora
Importing GPG key 0x4F2A6FD2 "Fedora Project <fedora@redhat.com>"
Is this ok [y/N] :

Example 2. Format of yum Public Key Import

Check the public key, and then press [y] to import the key and authorize the key for use. If you press [N] or [Enter] , yum stops without installing any packages.

To ensure that downloaded packages are genuine, yum verifies the digital signature of each package against the public key of the provider. Once all of the packages required for the transaction are successfully downloaded and verified, yum applies them to your system.

Transaction Log
Every completed transaction records the affected packages in the log file /var/log/yum.log. You may only read this file with root access.

4.1. Installing New Software with yum

To install the package tsclient, enter the command:

su -c 'yum install tsclient'

Enter the password for the root account when prompted.

To install the package group MySQL Database, enter the command:

su -c 'yum groupinstall "MySQL Database"'

Enter the password for the root account when prompted.

New Services Require Activation
When you install a service, Fedora does not activate or start it. To configure a new service to run on bootup, choose System → Administration → Services from the top desktop panel, or use the chkconfig and service command-line utilities.

4.2. Updating Software with yum

To update the tsclient package to the latest version, type:

su -c 'yum update tsclient'

Enter the password for the root account when prompted.

New Software Versions Require Reloading
If a piece of software is in use when you update it, the old version remains active until the application or service is restarted. Kernel updates take effect when you reboot the system.
Kernel Packages
Kernel packages remain on the system after they have been superseded by newer versions. This enables you to boot your system with an older kernel if an error occurs with the current kernel. To minimize maintenance, yum automatically removes obsolete kernel packages from your system, retaining only the current kernel and the previous version.

To update all of the packages in the package group MySQL Database, enter the command:

su -c 'yum groupupdate "MySQL Database"'

Enter the password for the root account when prompted.

Updating the Entire System
To update all of the packages on your Fedora system, use the commands described in Section 6, “Updating Your System with yum”.

4.3. Removing Software with yum

To remove software, yum examines your system for both the specified software, and any software which claims it as a dependency. The transaction to remove the software deletes both the software and the dependencies.

To remove the tsclient package from your system, use the command:

su -c 'yum remove tsclient'

Enter the password for the root account when prompted.

To remove all of the packages in the package group MySQL Database, enter the command:

su -c 'yum groupremove "MySQL Database"'

Enter the password for the root account when prompted.

Data and Configuration File Retention
The removal process leaves user data in place but may remove configuration files in some cases. If a package removal does not include the configuration file, and you reinstall the package later, it may reuse the old configuration file.
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5. Searching for Packages with yum

Use the search features of yum to find software that is available from the configured repositories, or already installed on your system. Searches automatically include both installed and available packages.

The format of the results depends upon the option. If the query produces no information, there are no packages matching the criteria.

5.1. Searching by Package Name and Attributes

To search for a specific package by name, use the list function. To search for the package tsclient, use the command:

su -c 'yum list tsclient'

Enter the password for the root account when prompted.

To make your queries more precise, specify packages with a name that include other attributes, such as version or hardware architecture. To search for version 0.132 of the application, use the command:

su -c 'yum list tsclient-0.132'

Valid Package Attributes
Refer to Section 2.4, “Understanding Package Names” for information on package name formats and the attributes that they include.

5.2. Advanced Searches

If you do not know the name of the package, use the search or provides options. Alternatively, use wild cards with any yum search option to broaden the search criteria.

The search option checks the names, descriptions, summaries and listed package maintainers of all of the available packages to find those that match. For example, to search for all packages that relate to Palm Pilots, type:

su -c 'yum search PalmPilot'

Enter the password for the root account when prompted.

The provides function checks both the files included in the packages and the functions that the software provides. This option requires yum to download and read much larger index files than with the search option.

To search for all packages that include files called libneon, type:

su -c 'yum provides libneon'

To search for all packages that either provide a MTA (Mail Transport Agent) service, or include files with mta in their name:

su -c 'yum provides MTA'

For each command, at the prompt enter the password for the root account.

Use the standard wild-card characters to run any search option with a partial word or name: ? to represent any one character, and * to mean zero or more characters. Always add the escape character \ before wild-cards.

To list all packages with names that begin with tsc, type:

su -c 'yum list tsc\*'

5.3. Understanding Matches

Searches with yum show all of the packages that match your criteria. Packages must meet the terms of the search exactly to be considered matches, unless you use wild-cards.

For example, a search query for shadowutils or shadow-util would not produce the package shadow-utils. This package would match and be shown if the query was shadow-util\?, or shadow\*.

Previous Page - 4. Managing Software with yum Table of Contents Next Page - 6. Updating Your System with yum

6. Updating Your System with yum

Use the update option to upgrade all of your Fedora system software to the latest version with one operation.

To perform a full system update, type this command:

su -c 'yum update'

At the prompt, enter the root password.

6.1. Automatically Updating Your System

The yum package supplied with Fedora includes scripts to perform full system updates every day. To activate automatic daily updates, enter this command:

su -c '/sbin/chkconfig --level 345 yum on; /sbin/service yum start'

At the prompt, enter the password for the root account.

How Daily Updates are Run
There is no separate yum service that runs on your system. The command given above enables the control script /etc/rc.d/init.d/yum. This control script activates the script /etc/cron.daily/yum.cron, which causes the cron service to automatically begin a system update at 4am each day.
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7. Configuring Access to Software Repositories

Fedora systems automatically use the Fedora Project repositories. If the Fedora Project does not supply packages for a product, the manufacturer may provide or recommend a separate repository. Members of the community also maintain repositories to provide packages for Fedora systems. For example, http://www.jpackage.org/ distributes popular Java software as packages.

7.1. Adding a Repository as a Package Source

To add an extra repository, place a definition file in the /etc/yum.repos.d/ directory on your system. Package providers make the definition files for their repositories available on their web sites.

Definition File Extension
The names of repository definition files end with .repo.

You must have root access to add a file to the definitions directory. To copy the definition file example.repo, type this command:

su -c 'cp example.repo /etc/yum.repos.d/'

At the prompt, enter the password for the root account.

The configuration file for each repository should include a gpgkey setting. This setting specifies the location of a public key that verifies the packages provided by that repository. This public key is automatically imported the first time that you install software from the repository. If the configuration file provided does not include this setting, refer to Section 7.2, “Manually Authorizing Package Sources”.

7.2. Manually Authorizing Package Sources

To manually add a public key to your rpm keyring, use the import feature of the rpm utility. To import the file GPG-PUB-KEY.asc, type the following command:

su -c 'rpm --import GPG-PUB-KEY.asc'

At the prompt, enter the password for the root account.

You may also import public keys directly from a web site. For example, to import the file GPG-PUB-KEY.asc on the web site www.therepository.com, use this command:

su -c 'rpm --import http://www.therepository.com/GPG-PUB-KEY.asc'

At the prompt, enter the root password.

Importing the Fedora Key
To add the Fedora public key to the rpm keyring on Fedora systems, run the command su -c 'rpm --import /usr/share/rhn/RPM-GPG-KEY-fedora'.

7.3. Understanding Repository Compatibility

The Fedora Package Collection includes several thousands of packages which are compatible with each other. Third-party packages should be compatible with these Fedora Project packages, unless the provider specifically states otherwise.

Always read the web site of the repository for information on package compatibility before you add it as a package source. Separate repository providers may offer different and incompatible versions of the same software. Third-party repositories may also provide alternative packages for software that is included in Fedora repositories.

Alternative packages may contain versions of the software that function differently from the version in the Fedora Project packages. Determine the benefits and potential incompatibilities before replacing Fedora Project packages with alternative versions.

Incompatible Repositories
If you configure your system to use incompatible repositories yum operations may fail.

Packages built for one version of Fedora are usually not compatible with other versions of Fedora. The web site of the provider should specifically state which versions of Fedora they support.

Old Versions of yum and Current Repositories
The data format for repository indexes changed with version 2.1 of yum. This was the version supplied with Fedora Core 3. Repository providers should specify the versions of Fedora that they support. To confirm that an unlabeled repository is compatible with current versions of yum, check that it has a sub-directory called repodata/.

7.4. Disabling or Removing Package Sources

Set enabled=0 in a definition file to prevent yum from using that repository. The yum utility ignores any definition file with this setting.

To completely remove access to a repository:

  1. Delete the relevant file from /etc/yum.repos.d/.
  2. Delete the cache directory from /var/cache/yum/.
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8. Installing Software from an Isolated Package

Use repositories and the standard yum commands to locate and install new software, unless the software package is not available from any repository. In these cases, use the localinstall function to install the software from the package file.

Public Key is Required
Ensure that the public key for the package source has been imported before you install a package without a repository. Refer to Section 7.2, “Manually Authorizing Package Sources”.

Enter this command to install the package tsclient-0.132-4.i386.rpm:

su -c 'yum localinstall tsclient-0.132-4.i386.rpm'

At the prompt, enter the root password.

Previously Installed Software is Updated
If the package provides a later version of software that is already installed on your system, yum updates the installed software.

If the package requires software that is not installed on your system, yum attempts to meet the dependencies with packages from the configured repositories. You may need to manually download and install additional packages in order to satisfy all of the dependencies.

Maintaining Manually Installed Software
If you install software that is not provided by a repository, yum update cannot automatically upgrade it as new versions become available. To ensure that you have the latest packages, subscribe to e-mail or RSS services that notify you when new versions are released.
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9. Customizing yum

To change the behavior of yum, you may either edit the configuration files, or install plugins. Plugins enable developers to add new features to yum.

9.1. Editing the yum Configuration

The file /etc/yum.conf provides the main configuration for yum. Settings in a repository definition file override the main configuration for those operations that use the defined repository.

To edit /etc/yum.conf, run a text editor with root privileges. This command opens /etc/yum.conf with gedit, the default text editor for Fedora desktop systems:

su -c 'gedit /etc/yum.conf'

Enter the password for the root account when prompted.

The main configuration file provides the settings that apply to all yum operations. These include caching options, and proxy server settings. The directory /etc/yum.repos.d/ holds definition files for each repository that yum uses. Plugins use the configuration files in the directory /etc/yum/pluginconf.d/.

The following sections in this document provide further information on configuring yum:

Further Documentation
Refer to the man page for yum.conf for a complete list of the configuration options supported by yum.

9.2. Working with yum Plugins

Each yum plugin is a single file, written in the Python programming language. You may download plugins from the yum project Web site, or from third-party providers. The yum project maintains a list of plugins on the page http://wiki.linux.duke.edu/YumPlugins.

Plugin File Extension
The names of yum plugin files end with .py, the standard extension for Python scripts.

To install a plugin, copy it to the directory /usr/lib/yum-plugins/. Create a configuration file for the plugin in the directory /etc/yum/pluginconf.d/. Save the configuration file with the same name as the plugin, but with the extension .conf.

root Privileges Required
You must have root access to add files to the directories /usr/lib/yum-plugins/ and /etc/yum/pluginconf.d/.

For example, to copy the plugin exampleplugin.py, enter the command:

su -c 'cp exampleplugin.py /usr/lib/yum-plugins/'

Enter the password for the root account when prompted.

You may then create a configuration file for the plugin with a text editor. This example uses gedit, the default text editor for Fedora desktop systems:

su -c 'gedit /etc/yum/pluginconf.d/exampleplugin.conf'

Enter the password for the root account when prompted.

Each plugin configuration file includes the enabled setting. Some plugins also require additional settings. To determine the correct settings, either refer to the documentation supplied with the plugin, or read the plugin file itself with any text editor.

[main] 
enabled=1
anotheroption=0

Example 3. Example Plugin Configuration File

9.3 Useful Plugins for Fedora Users

Yum is easily extensible through plugins and a number of plugins have been written by many developers. These plugins advance the core capabilities of Yum and add more features. This section covers the plugins that are useful to Fedora users.

Downloadonly Plugin

This plugin tells yum to download the package(s) from a mirror server but stop after downloading. Yum will not install the package. Usage of this plugin is:

su -c 'yum install <package> --downloadonly'

Installonlyn Plugin

Usually software package updates work by removing the older package, retaining the configuration and installing the newer version of a package. Kernel packages are more unique since newer versions can be installed in parallel. Every release of Fedora usually receives a number of kernel updates during its lifecycle due to the general policy of staying close to upstream projects. Each of these kernel updates then occupy space and over time will clutter the initial boot loader options. To prevent this, the installonlyn plugin leaves "n" number of kernel packages by default removing the oldest ones first sequentially on updates. Fedora Core 5 onwards installs this plugin by default. In Fedora, this plugin retains the current kernel and two latest updates. You can disable this plugin or configure it to retain a different number of kernels by setting the value in the file /etc/yum/pluginconf.d/installonlyn.conf

Fastest Mirror Plugin

Yum in Fedora uses a dynamic server side mirror management infrastructure that distributes the bandwidth consumptions on each of these mirrors by automatically directing the update to one of the geographically closest mirrors. This mirror is automatically checked against the master server for consistency.

The fastest mirror plugin enhances the speed of updates by maintaining a local offline hostfile cache of the speed of the mirrors. It sorts the mirror list by speed and prioritizes the faster ones for package downloads. This plugin is not installed by default. For installing it, use the following command or from the Applications menu use Add/Remove Software".

su -c 'yum install yum-fastestmirror'

You can configure various settings of this plugin in the file /etc/yum/pluginconf.d/fastestmirror.conf

Security Plugin

This plugin extends yum to allow lists and updates to be limited using security relevant criteria. This may be important to you if you are using Fedora in a production mode and you don't want to break your software with an untested upgrade.

For installing it, use the following command or from the Applications menu use Add/Remove Software".

su -c 'yum install yum-security'

There are two yum commands that are used with this plugin:

  • info-sec
  • list-sec

Both of these commands take these sub-commands:

  • <advisory> [advisory...]
  • bugzillas
  • cves
  • security

Examples

To list all updates that are security relevant, and get a return code on whether there are security updates use:

su -c 'yum --security check-update'

To apply updates that are security relevant use:

su -c 'yum --security update'

To get a list of all BZs that are fixed for packages you have installed use:

su -c 'yum list-sec bugzillas'

To get the information on advisory FEDORA-2707-4567 use:

su -c 'yum info-sec FEDORA-2707-4567'

For additional information, view the man page:

man yum-security

YumUtils

Yum-Utils is a collection of tools written using the Yum API. The individual tools are explained below. For additional information on these tools you can consult the manual man <package> or visit the YUM website .

Package Cleanup

Package-Cleanup is a program used for cleaning up RPMs that you have installed on your computer. By using one of the many options available you can easily find problems in your current installed packages. Package-Cleanup will list dependency problems, find RPMs that aren't being relied upon by any other RPM, locate installed packages which are not available from currently configured repositories, and remove old kernel and kernel-devel packages.

Repo-RSS

Repo-RSS is a program for generating RSS feeds for Yum repositories. You can specify the name, URL, title, description of the feed, and the number of days to consider recent.


Repoquery

Repoquery is a program for querying information from YUM repositories in much the same was as RPM queries.


Reposync

Reposync is used to synchronize a remote yum repository to a local directory. Reposync uses yum to retrieve these packages and can even create custom requests for the newest packages, only updates, or a combination of these and more.

Yum-Builddep

Yum-Builddep is a program which installs the RPMs needed to build a package. The source RPM for the package can be from the Yum repository or from a local source.

Yum-Complete-Transaction

Yum-Complete-Transaction is a program that attempts to complete aborted or incomplete transactions on a system and attempts to complete them. By using the transaction logs in /var/lib/yum this program will attempt to complete the most recent unfinished transaction first. You can run it more than once to clean up all unfinished transactions.

YumDownloader

Yum-Downloader is a utility that downloads RPMs from Yum repositories. You can have the utility show you the URL from where the RPM would be downloaded from, have it automatically resolve dependencies, and allow you to also download the source for the RPMs.

Changelog Plugin

When Fedora developers provide a update to a existing package, they describe the changes in the new update in the software package change log. This plugin helps you see the package changelog before doing a update. This plugin is not installed by default. For installing it, use the following command or from the Applications menu use Add/Remove Software".

su -c 'yum install yum-changelog'

Sample output:

su -c 'yum update frysk --changelog'
Loading "changelog" plugin
Setting up Update Process
Setting up repositories
Reading repository metadata in from local files
Resolving Dependencies
--> Populating transaction set with selected packages. Please wait.
---> Package frysk.i686 0:0.0.1.2006.12.01.rh1-1.fc6 set to be updated
--> Running transaction check

Changes in packages about to be updated:

frysk - 0.0.1.2006.12.01.rh1-1.fc6.i686
* Sat Dec  2 03:30:00 2006 Stepan Kasal <skasal@redhat.com> - 0.0.1.2006.12.01.rh1-1
- New upstream version.
- Resolves: #211288.


* Fri Dec  1 03:30:00 2006 Stepan Kasal <skasal@redhat.com> - 0.0.1.2006.11.30.rh1-1
- New upstream version.
- The stamp file for glade files has been renamed.



Dependencies Resolved

=============================================================================
Package                 Arch       Version          Repository        Size
=============================================================================
Updating:
frysk                   i686       0.0.1.2006.12.01.rh1-1.fc6  updates           7.5 M

Transaction Summary
=============================================================================
Install      0 Package(s)
Update       1 Package(s)
Remove       0 Package(s)

Total download size: 7.5 M
Is this ok [y/N] :

By default, the package changelog is showed before doing an update. If you prefer to see the changelog after doing an update instead, you can change the setting from when=pre to when=post in the file /etc/yum/pluginconf.d/changelog.conf. A sample output after the configuration has been changed from 'pre' to 'post'

su -c 'yum update frysk --changelog'
Loading "changelog" plugin
Setting up Update Process
Setting up repositories
Reading repository metadata in from local files
Resolving Dependencies
--> Populating transaction set with selected packages. Please wait.
---> Package frysk.i686 0:0.0.1.2006.12.01.rh1-1.fc6 set to be updated
--> Running transaction check

Dependencies Resolved

=============================================================================
Package                 Arch       Version          Repository        Size
=============================================================================
Updating:
frysk                   i686       0.0.1.2006.12.01.rh1-1.fc6  updates           7.5 M

Transaction Summary
=============================================================================
Install      0 Package(s)
Update       1 Package(s)
Remove       0 Package(s)

Total download size: 7.5 M
Is this ok [y/N] : y
Downloading Packages:
(1/1): frysk-0.0.1.2006.1 100% |=========================| 7.5 MB    04:24
Running Transaction Test
Finished Transaction Test
Transaction Test Succeeded
Running Transaction
Updating  : frysk                        ######################### [1/2] 
Cleanup   : frysk                        ######################### [2/2] 

Changes in updated packages:

frysk - 0.0.1.2006.12.01.rh1-1.fc6.i686
* Sat Dec  2 03:30:00 2006 Stepan Kasal <skasal@redhat.com> - 0.0.1.2006.12.01.rh1-1
- New upstream version.
- Resolves: #211288.


* Fri Dec  1 03:30:00 2006 Stepan Kasal <skasal@redhat.com> - 0.0.1.2006.11.30.rh1-1
- New upstream version.
- The stamp file for glade files has been renamed.



Updated: frysk.i686 0:0.0.1.2006.12.01.rh1-1.fc6
Complete!

Skip-broken Plugin

Yum by default checks to make all dependencies are resolved before doing a update, however on occasions like when testing the Fedora development tree or when there is a known dependency issue in the software repository it is useful to skip the broken dependencies automatically instead of having to manually specify the exact packages to ignore in the command line or yum configuration file. The skip-broken plugin helps do that. This plugin is not installed by default. For installing it, use the following command or from the Applications menu use Add/Remove Software".

su -c 'yum install yum-skip-broken'

You can use this plugin doing a update by specifying the following command line argument.

su -c 'yum update --skip-broken'

You can disable this plugin by changing the option in the file /etc/yum/pluginconf.d/skip-broken.conf

Allowdowngrade Plugin

The core Yum package manager does not have the functionality to let users downgrade a package. This is a design choice to favor robustness over the additional functionality. Unlike package updates, downgrades are not tested usually and hence may not have the desired effect. However advanced users would still find this feature useful to recover out of a broken update. This plugin adds the ability to perform downgrades of packages in Fedora. This plugin is not installed by default. For installing it, use the following command or from the Applications menu use Add/Remove Software".

su -c 'yum install yum-allowdowngrade'

You can use this plugin doing a update by specifying the following command line argument.

su -c 'yum update -allow-downgrade'

You can disable this plugin by changing the option in the file /etc/yum/pluginconf.d/allowdowngrade.conf

Notification and Auto Downloading, Installing of Updates

An interesting service is that of yum-updatesd. Yum-Updatesd will notify you of pending updates and can even be setup to automatically download and install the updates for you.

All settings are stored in /etc/yum/yum-updatesd.conf and the file should look like this:

[main] 
run_interval = 3600
updaterefresh = 600

emit_via = dbus
dbus_listener = yes

do_update = no
do_download = no
do_download_deps = no

Because yum-updatesd runs as a service, you must restart the service after editing /etc/yum/yum-updatesd.conf.

su -c '/sbin/service yum-updatesd restart'

Disabling All Plugins

If you would like to disable all the plugins while running Yum, you can use the following command line argument

su -c 'yum update --noplugins'

Developing New Plugins

If you are interested in developing your own plugins to add new features or change the behavior of Yum, refer to the guidelines at http://yum.baseurl.org/wiki/WritingYumPlugins. Join the yum development list at http://lists.baseurl.org/mailman/listinfo/yum-devel to collaborate with Yum developers.

Previous Page - 8. Installing Software from an Isolated Package Table of Contents Next Page - 10. Working with yum Caching

10. Working with yum Caching

By default, current versions of yum delete the data files and packages that they download, after these have been successfully used for an operation. This minimizes the amount of storage space that yum uses. You may enable caching, so that yum retains the files that it downloads in cache directories.

Caches provide three advantages:

  • The performance of yum increases
  • You may carry out yum operations without a network connection, by using only the caches
  • You may copy packages from the caches and reuse them elsewhere

By default, yum stores temporary files under the directory /var/cache/yum/, with one subdirectory for each configured repository. The packages/ directory within each repository directory holds the cached packages. For example, the directory /var/cache/yum/development/packages/ holds packages downloaded from the development repository.

Clearing the yum Caches
Cached files use disk space until removed. You may wish to periodically clear the yum caches to recover capacity. Refer to Section 10.3, “Clearing the yum Caches” for information on clearing the caches.

If you remove a package from the cache, you do not affect the copy of the software installed on your system.

10.1. Enabling the Caches

To configure yum to retain downloaded files rather than discarding them, set the keepcache option in /etc/yum.conf to 1:

keepcache=1

Refer to Section 9.1, “Editing the yum Configuration” for more information on editing the yum configuration file.

Once you enable caching, every yum operation may download package data from the configured repositories. To ensure that the caches have a set of package data, carry out an operation after you enable caching. Use a list or search query to download package data without modifying your system.

10.2. Using yum in Cache-only Mode

To carry out a yum command without a network connection, add the -C option. This causes yum to proceed without checking any network repositories, and use only cached files. In this mode, yum may only install packages that have been downloaded and cached by a previous operation.

To search for the package tsclient without using a network connection, enter the command:

su -c 'yum -C list tsclient'

Enter the password for the root account when prompted.

Cache-only Mode Requires Cached Data
Cache-only mode requires package data to exist in the caches. If you enable caching, every yum operation may update the data files, unless cache-only mode is specified for the operation.

10.3. Clearing the yum Caches

If you configure it to do so, yum retains the packages and package data files that it downloads, so that they may be reused in future operations without being downloaded again. To purge the package data files, use this command:

su -c 'yum clean headers'

Run this command to remove all of the packages held in the caches:

su -c 'yum clean packages'

When using these commands, at the prompt, enter the password for the root account.

Purging cached files causes those files to downloaded again the next time that they are required. This increases the amount of time required to complete the operation.

Previous Page - 9. Customizing yum Table of Contents Next Page - 11. Using yum with a Proxy Server

11. Using yum with a Proxy Server

By default, yum accesses network repositories with HTTP. All yum HTTP operations use HTTP/1.1, and are compatible with web proxy servers that support this standard. You may also access FTP repositories, and configure yum to use an FTP proxy server. The squid package provides a proxy service for both HTTP/1.1 and FTP connections.

Modifying yum for Network Compatibility
Refer to the man page for yum.conf for information on HTTP settings that may be modified for compatibility with nonstandard web proxy servers. Alternatively, configure yum to use an FTP proxy server, and access repositories that support FTP. The Fedora repositories support both HTTP and FTP.

11.1. Configuring Proxy Server Access

To enable all yum operations to use a proxy server, specify the proxy server details in /etc/yum.conf. The proxy setting must specify the proxy server as a complete URL, including the TCP port number. If your proxy server requires a username and password, specify these by adding proxy_username and proxy_password settings.

The settings below enable yum to use the proxy server mycache.mydomain.com, connecting to port 3128, with the username yum-user and the password qwerty.

proxy=http://mycache.mydomain.com:3128
proxy_username=yum-user
proxy_password=qwerty

Example 4. Configuration File Settings for Using A Proxy Server

Older versions of yum may require a "/" after the port number: proxy=http://mycache.mydomain.com:3128/
Global Settings
If you define a proxy server in /etc/yum.conf, all users connect to the proxy server with those details when using yum.

11.2. Configuring Proxy Server Access for a Single User

To enable proxy access for a specific user, add the lines in the example box below to the user's shell profile. For the default bash shell, the profile is the file ~/.bash_profile. The settings below enable yum to use the proxy server mycache.mydomain.com, connecting to port 3128.

http_proxy="http://mycache.mydomain.com:3128"
export http_proxy

Example 5. Profile Settings for Using a Proxy Server

If the proxy server requires a username and password, add these to the URL. To include the username yum-user and the password qwerty, add these settings:

 # The Web proxy server, with the username and password for this account
http_proxy="http://yum-user:qwerty@mycache.mydomain.com:3128"
export http_proxy 

Example 6. Profile Settings for a Secured Proxy Server

The http_proxy Environment Variable
The http_proxy environment variable is also used by curl and other utilities. Although yum itself may use http_proxy in either upper-case or lower-case, curl requires the name of the variable to be in lower-case.
Previous Page - 10. Working with yum Caching Table of Contents Next Page - 12. Acknowledgements

12. Acknowledgements

Paul Frields edited this document. Timothy Murphy reviewed the beta release.

[Editor's Note: This applies to the original DocBook version]

Previous Page - 11. Using yum with a Proxy Server Table of Contents Next Page - Index