Install or enable EPEL Repo on Linux  – CentOS/RHEL/Scientific Linux

What is Extra Packages for Enterprise Linux (or EPEL)?
Extra Packages for Enterprise Linux (or EPEL) is a Fedora Special Interest Group that creates, maintains, and manages a high quality set of additional packages for Enterprise Linux, including, but not limited to, Red Hat Enterprise Linux (RHEL), CentOS and Scientific Linux (SL), Oracle Linux (OL).

How do I enable it under Linux CentOS or RHLE  server?

You need to install the following rpms as per your Enterprise Linux version.

For CentOS7/RHEL 7 version

yum install epel-release

if “yum install epel-release” fails
try

cd /tmp
wget https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm
ls *.rpm
yum install epel-release-latest-7.noarch.rpm
or
rpm -ivh epel-release-latest-7.noarch.rpm

If you are running  CentOS6/RHEL6 version, enter:

$ cd /tmp
# wget http://download.fedoraproject.org/pub/epel/6/i386/epel-release-6-8.noarch.rpm
# rpm -ivh epel-release-6-8.noarch.rpm

If you are running  CentOS 5/RHEL5 version, enter:

# cd /tmp
# wget https://dl.fedoraproject.org/pub/epel/5/i386/epel-release-5-4.noarch.rpm
# rpm -ivh epel-release-5-4.noarch.rpm

If you are running CentOS4/EL4 version, enter:

The following may not be supported:

# cd /tmp
# wget http://download.fedoraproject.org/pub/epel/4/i386/epel-release-4-10.noarch.rpm
# rpm -ivh epel-release-4-10.noarch.rpm

Install epel*.rpm file using yum command

You can use the yum command instead of rpm command:

# yum install epel-release-6-8.noarch.rpm

Sample outputs:

 
 Dependencies Resolved
 
================================================================================
 Package            Arch         Version   Repository                      Size
================================================================================
Installing:
 epel-release       noarch       6-8       /epel-release-6-8.noarch        22 k
 
Transaction Summary
================================================================================
Install       1 Package(s)
 
Total size: 22 k
Installed size: 22 k
Is this ok [y/N]: y
Downloading Packages:
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
  Installing : epel-release-6-8.noarch                                      1/1 
  Verifying  : epel-release-6-8.noarch                                      1/1 
 
Installed:
  epel-release.noarch 0:6-8                                                     
 
Complete!

How do I list all enabled repos?

Type the following commands:

# yum repolist

sample output:

Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * base: centosmirror.netcup.net
 * epel: mirror.daniel-jost.net
 * extras: centosmirror.netcup.net
 * updates: centosmirror.netcup.net
repo id       repo name         status
base          CentOS-6 - Base   6,696
epel          Extra Packages for Enterprise Linux 6 - x86_64 12,255
extras        CentOS-6 - Extras 63
updates CentOS-6 - Updates      820

OR

# yum -v repolist | less

Please note that epel is your “EPEL Repo ID” .

How do I list all packages in EPEL repo?

Type the following command to list all packages from EPEL repo only:

# yum --disablerepo="*" --enablerepo="epel" list available

To search packages in epel repo only, enter:

# yum --disablerepo="*" --enablerepo="epel" search packageNameHere
# yum --disablerepo="*" --enablerepo="epel" search iftop

How do I use EPEL repo?
Simply use the yum commands to search or install packages from EPEL repo:

# yum search iftop
# yum update
# yum --disablerepo="*" --enablerepo="epel" install iftop

Sample outputs:

Loaded plugins: product-id, rhnplugin, subscription-manager
Updating certificate-based repositories.
epel/metalink                                                                                                                          |  13 kB     00:00     
epel                                                                                                                                   | 4.3 kB     00:00     
epel/primary_db                                                                                                                        | 4.1 MB     00:03     
Setting up Update Process
Resolving Dependencies
Running transaction check
Package dkms.noarch 0:2.0.10-1 will be updated
Package dkms.noarch 0:2.1.0.1-1.el6 will be an update
Package iftop.x86_64 0:0.17-1.el6 will be updated
Package iftop.x86_64 0:1.0-0.1.pre2.el6 will be an update
Finished Dependency Resolution

Dependencies Resolved

=====================================================================================================================================
 Package                            Arch                                Version                                       Repository                         Size
=====================================================================================================================================
Updating:
 dkms                               noarch                              2.1.0.1-1.el6                                 epel                               99 k
 iftop                              x86_64                              1.0-0.1.pre2.el6                              epel                               44 k

Transaction Summary
=====================================================================================================================================
Upgrade       2 Package(s)

Total download size: 144 k
Is this ok [y/N]: y
Downloading Packages:
(1/2): dkms-2.1.0.1-1.el6.noarch.rpm                                                                                                   |  99 kB     00:00     
(2/2): iftop-1.0-0.1.pre2.el6.x86_64.rpm                                                                                               |  44 kB     00:00     
-------------------------------------------------------------------------------------------------------------------------------------
Total                                                                                                                         543 kB/s | 144 kB     00:00     
warning: rpmts_HdrFromFdno: Header V3 RSA/SHA256 Signature, key ID 0608b895: NOKEY
Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-6
Importing GPG key 0x0608B895:
 Userid : EPEL (6) <epel@fedoraproject.org>
 Package: epel-release-6-5.noarch (installed)
 From   : /etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-6
Is this ok [y/N]: y
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
Warning: RPMDB altered outside of yum.
  Updating   : dkms-2.1.0.1-1.el6.noarch                                                                                                                  1/4 
  Updating   : iftop-1.0-0.1.pre2.el6.x86_64                                                                                                              2/4 
  Cleanup    : dkms-2.0.10-1.noarch                                                                                                                       3/4 
  Cleanup    : iftop-0.17-1.el6.x86_64                                                                                                                    4/4 
Installed products updated.

Updated:
  dkms.noarch 0:2.1.0.1-1.el6                                                 iftop.x86_64 0:1.0-0.1.pre2.el6                                                

Complete!