14.4. Configuring yum

By default, yum is configured through /etc/yum.conf. The following is an example of a typical /etc/yum.conf file:
[main]
cachedir=/var/cache/yum
keepcache=0
debuglevel=2
logfile=/var/log/yum.log
distroverpkg=redhat-release
tolerant=1
exactarch=1
obsoletes=1
gpgcheck=1
plugins=1
metadata_expire=1800
[myrepo]
name=RHEL 5 $releasever - $basearch
baseurl=http://local/path/to/yum/repository/
enabled=1
A typical /etc/yum.conf file is made up of two types of sections: a [main] section, and a repository section. There can only be one [main] section, but you can specify multiple repositories in a single /etc/yum.conf.

14.4.1.  [main] Options

The [main] section is mandatory, and there must only be one. For a complete list of options you can use in the [main] section, refer to man yum.conf.
The following is a list of the most commonly-used options in the [main] section.
cachedir
This option specifies the directory where yum should store its cache and database files. By default, the cache directory of yum is /var/cache/yum.
keepcache=<1 or 0>
Setting keepcache=1 instructs yum to keep the cache of headers and packages after a successful installation. keepcache=1 is the default.
reposdir=<absolute path to directory of .repo files>
This option allows you to specify a directory where .repo files are located. .repo files contain repository information (similar to the [repository] section of /etc/yum.conf).
yum collects all repository information from .repo files and the [repository] section of the /etc/yum.conf file to create a master list of repositories to use for each transaction. Refer to Section 14.4.2, “ [repository] Options” for more information about options you can use for both the [repository] section and .repo files.
If reposdir is not set, yum uses the default directory /etc/yum.repos.d.
gpgcheck=<1 or 0>
This disables/enables GPG signature checking on packages on all repositories, including local package installation. The default is gpgcheck=0, which disables GPG checking.
If this option is set in the [main] section of the /etc/yum.conf file, it sets the GPG checking rule for all repositories. However, you can also set this on individual repositories instead; i.e., you can enable GPG checking on one repository while disabling it on another.
assumeyes=<1 or 0>
This determines whether or not yum should prompt for confirmation of critical actions. The default if assumeyes=0, which means yum will prompt you for confirmation.
If assumeyes=1 is set, yum behaves in the same way that the command line option -y does.
tolerant=<1 or 0>
When enabled (tolerant=1), yum will be tolerant of errors on the command line with regard to packages. This is similar to the yum command line option -t.
The default value for this is tolerant=0 (not tolerant).
exclude=<package name/s>
This option allows you to exclude packages by keyword during installation/updates. If you are specifying multiple packages, this is a space-delimited list. Shell globs using wildcards (for example, * and ?) are allowed.
retries=<number of retries>
This sets the number of times yum should attempt to retrieve a file before returning an error. Setting this to 0 makes yum retry forever. The default value is 6.