YUM Overview

YUM (Yellowdog Updater Modified) is a package manager offering a fast way for installing, updating, and removing packages. The yum command has a very simple interface and functions similar to rpm, but yum additionally manages all of the dependencies for you. Yum will detect if dependencies are required for the installation of an application and, if need be, fetch the required dependency and install it. Yum has the ability to support multiple repositories for packages and has a simple configuration.

YUM is configured through the /etc/yum.conf configuration file. A sample of the configuration file follows. Repositories may be added and modified through the /etc/yum.repos.d directory:

# cat /etc/yum.conf [main] cachedir=/var/cache/yum keepcache=0 debuglevel=2 logfile=/var/log/yum.log exactarch=1 obsoletes=1 gpgcheck=1 plugins=1 installonly_limit=3 # This is the default. If you make this bigger yum won't see if the metadata # is newer on the remote and so you'll "gain" the bandwidth of not having to # download the new metadata and "pay" for it by yum not having correct # information. # It is especially important, to have correct metadata, for distributions # like Fedora that don't keep old packages around. If you don't like this # checking interrupting your command line usage, it's much better to have # something manually check the metadata once an hour (yum-updatesd will do this). # metadata_expire=90m # PUT YOUR REPOS HERE OR IN separate files named file.repo # in /etc/yum.repos.d ...

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