Linux: What is the EPEL

scottalanmiller

In the Red Hat Enterprise Linux and CentOS circles, there is a need for a second tier of packages to compliment the small, tight, heavily tested and guaranteed base packages included by Red Hat with the RHEL distribution. This is handled by the Fedora team, also at Red Hat, who are already managing a large ecosystem of packages for the Fedora Linux distribution that gets locked in and turned into the tighter, slower releasing RHEL and CentOS packages. Since Fedora is already selecting and maintaining these extra packages, they do so for RHEL and CentOS as well.

In the same way that the core RHEL packages are selected and "frozen" for the core RHEL distribution, the Fedora team makes this large number of "extra" packages available in the same way, locked to the RHEL core.

The EPEL is an official add on repository of these packages which is commonly added onto RHEL or CentOS to provide these distros with access to a list of software similar to that of Fedora itself. The packages in the EPEL are not as heavily tested as those in the RHEL core, but are tested and maintained and patched with great care. The EPEL is not official under Red Hat standard support contracts, but is supported for use and often recommended and Red Hat customers can request that EPEL packages be added to support (I've done this personally) when needed.

Using the EPEL is as easy as this command:

yum install epel-release

Once added, the repository is connected and enabled and installing packages that exist in the EPEL, but not in the RHEL / CentOS core is transparent. Here is an example that will fail before adding the EPEL and succeed after: