Exploring the yum package manager
Plugins and Repositories
Yum has many extensions that you can install easily from the repository. When you download a file, for example, the Fastestmirror plugin performs a background search for the fastest mirror server. To install and enable the plugin, type yum install yum-fastestmirror.
If multiple mirrors are available, install the Priorities plugin, which lets you control the priorities of the individual repositories:
yum -y install yum-priorities
After giving this command, you will find a priorities.conf file in /etc/yum/pluginconf.d/:
[main] enabled = 1 check_obsoletes = 1
To avoid legal issues, Fedora only provides software available under a free license. The default Fedora repositories do not include proprietary programs or, for licensing reasons, many other free applications, such as mplayer. Fortunately, some of these programs are available through third-party suppliers.
The most popular repositories include Livna, RPMforge, Dribble, freshrpms, and ATrpms. In Fedora 10, Dribble, freshrpms, and Livna combined to form a single repository known as RPM Fusion . The unofficial Fedora FAQ page  describes how to add Livna, or RPM Fusion, as package source; for Fedora 10, simply enter:
# rpm -Uvh http://rpm.livna.org/livna-release-10.rpm
The configuration files for the various repositories are stored in /etc/yum-repos.d/. In these configuration files, you can enable or disable individual repositories with the enabled=1 or enabled=0 entries. Most repository files include several entries, but typically you only need the top one.
After completing a standard Fedora installation, including the RPM Fusion repository, you will have three configuration files below /etc/yum.repos.d/: fedora.repo, fedora-updates.repo, and livna.repo. Just set the top lines to enabled=1 and the others to enabled = 0.
Alternatively, you can delete and disable all additional repository entries by typing:
# rpm -e yum-priorities yum-fedorafaq livna-release
The yum-priorities plugin mentioned earlier is used here. yum repolist gives you a list of all enabled repositories.
Upgrading with Yum
Yum lets you upgrade a Fedora system to the next version on the fly. Unfortunately, this option sometimes doesn't work properly and typically requires some manual attention.
If you do decide to rely on yum upgrading for you, start by flushing your yum cache and updating the package sources. Listing 4 gives a short overview of the steps required for upgrading to Fedora 11. You'll find a more detailed howto in the Fedora wiki .
Upgrading to Fedora 11
yum clean all rpm -Uhv ftp://download.fedora.redhat.com/pub/fedora/linux/releases/11/Fedora/i386/os/Packages/fedora-release-*.noarch.rpm yum upgrade
If you use Ubuntu and occasionally need to compile something, you will be familiar with the build-essential package. build-essential is not a Debian package in the strictest sense, but a meta package that automatically installs a software selection. Fedora has a similar feature but calls it package groups.
yum grouplist gives you a list of available package groups. Note the Development Tools group, which you can install by typing:
# yum -y groupinstall 'Development Tools'
If you want to install all the available games, or maybe all the available office programs, just pick the right category from the list and install as described above.
Read full article as PDF:Yum_Package_Manager.pdf (444.49 kB)
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