Repositories¶
To install packages on a Linux server then the packages will need to be available in the enabled repositories on the server. On a Red Hat based server, you can see the installed repositories by viewing the files located in the below directory.
/etc/yum.repos.d/
Even though these repositories are installed on the server this does not definitively mean that they are enabled on the server. On a Red Hat based server you will be able to see whether or not the repository is enabled by viewing the file with a text viewer such as less.
less /etc/yum.repos.d/centos-base.repo
You will then be able to see whether or not it is enabled by viewing the value for the enabled configuration. If it is set to 0 then it is disabled and if it is set to 1 then it is enabled.
You can also enable a repository while attempting to install by adding the --enablerepo to the Yellowdog Updater, Modified (yum) command. For example, to enable the Extra Packages for Enterprise Linux (EPEL) repository you can use the below command.
yum update --enablerepo=epel
Install other repositories¶
There are a variety of different methods available to install other repositories. As this is a basic guide it will only glance over two methods with are yum and wget. This guide will explain how to install the EPEL repository using both methods.
To use yum to install the EPEL repository you can simply use the below command:
yum install epel-release
To use wget to install the EPEL repository, you will need to ensure that you are installing the correct repository for the correct OS version. For example, if you are using CentOS 6, you will need to ensure that you are installing the EPEL repository for CentOS 6. The first command below downloads the Red Hat Package Manager (RPM) package for EPEL and then the second command installs the repository using the .rpm file.
wget http://download.fedoraproject.org/pub/epel/6/i386/epel-release-6-8.noarch.rpm
rpm -uvh epel-release-6-8.noarch.rpm