Add / Install Epel repo to CentOS 7

With CentOS 7 the process of adding the Epel repo has been simplified, you now install the repo with the CentOS package manager yum. With this new method, you don’t need to worry about manually re-adding the repo if it has gone out of date, a simple yum update will update the repo.

To add the Epel repo to your CentOS 7 installation simply issue the following at shell: