Recommended Read: Examples on how to use YUM command in Linux

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There are two methods using which we can install the EPEL repository on the Linux system,

1- Using the packages from default repositories

2- Using rpm package

1- Using the packages from the default repositories

To install the package from default repositories, use the following command,

CentOS/RHEL 6/7

# yum install epel-release

CentOS/RHEL 8

# dnf install epel-release

This command will work most of the times but I have faced an issue with some versions where this might not work. So if this does not work for you, then you can use the second method.

2- Using RPM packages

For this method, we will directly install the RPM package for epel repository. Based on the version, use one of the following commands,

RHEL/CentOS 6:

# yum install https://dl.fedoraproject.org/pub/epel/epel-release-latest-6.noarch.rpm

RHEL/CentOS 7:

# yum install https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm

Epel also recommends for RHEL 7, to enable the optional, extras, and HA repositories since EPEL packages may depend on packages from these repositories, using the following command,

# subscription-manager repos –enable “rhel-*-optional-rpms” –enable “rhel-*-extras-rpms” –enable “rhel-ha-for-rhel-*-server-rpms”

RHEL/CentOS 8:

# yum install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm

Note:- EPEL also recommends for RHEL 8, to enable the code ready-builder-for-rhel-8-*-rpms repository since EPEL packages may depend on packages from it. To install it, use the following commands,

# ARCH=$( /bin/arch )

# subscription-manager repos –enable “codeready-builder-for-rhel-8-${ARCH}-rpms”

Note:- For CentOS 8, EPEL recommends to also enable the PowerTools repository since EPEL packages may depend on packages from it, run the following command to enable power tools,

# dnf config-manager –set-enabled PowerTools

Check repository

Once the EPEL repository has been installed, we can check it by executing the following command,

RHEL/CentOS 6/7

# yum repolist

RHEL/CentOS 8

# dnf repolist epel

We can now install the packages available in the EPEL repository. Please share this tutorial, or if you have any questions, concerns or suggestions, please send them to us using the comment box below.

The post Install EPEL repository on CentOS/RHEL 6, 7 & 8 appeared first on The Linux GURUS.

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Also Read: How to install Java on CentOS & RHEL

Before we learn how to install JAVA on Ubuntu, we must know the types of java available to install. There are two different types of java versions we can install.

Two versions being,

JAVA JRE (Java Run Time Environment) – JRE is used when you only need to run java based applications.

JAVA JDK (Java Development Kit) – is used for developing Java-based applications. It included JRE, debugging tool & some other libraries.

Moreover, there are two types of java available that we can install OPENJDK Java & Oracle java. Both are similar & provide almost the same functionalities barring for some additional features in Enterprise versions. We will learn to install both the java types in this tutorial.

OpenJDK installation

Java 11

To install OpenJDK java on Ubuntu, we need to execute the following commands from the terminal,

$ sudo apt-get update

$ sudo apt-get install default-jdk

This will install the default java JDK i.e. version 11 on Ubuntu system. If we need to install the java 11 jre, then we need to execute the following command,

$ sudo apt install default-jre

Java 8

To install java 8 on the systems, we need to run the following command,

$ sudo apt-get update

$ sudo apt-get install openjdk-8-jdk

& to install JRE, use the following command,

$ sudo apt-get install openjdk-8-jre

Oracle Java Installation

Oracle Java is not available on the default Ubuntu repositories & we need to install other custom repositories to be able to install java on Ubuntu. Install the repository first with the following command,

$ sudo apt install software-properties-common

$ sudo add-apt-repository ppa:linuxuprising/java

Next update system repositories,

$ sudo apt-get update

& install java on Ubuntu system,

$ sudo apt-get install oracle-java11-installer

Java is now installed on the system. The next part is configuring the default java for the systems as you might have more than one java version installed on the system.

Configuring default Java

Command to configure the default java is,

# alternatives –config java

Then you should get the java versions installed on the system, type the number mentioned against the java version & press enter to make it the default versions. This will change the java versions to one that you want. We end this tutorial on how to install java. Please do let us know if you have questions, queries or suggestions using the comment box below.

The post How to install JAVA on Ubuntu appeared first on The Linux GURUS.

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Before we learn about java installation, we must know the types of java available to install. There are two different types of java versions we can install. Two versions being,

JAVA JRE (Java Run Time Environment) – JRE is used when you only need to run java based applications.

JAVA JDK (Java Development Kit) – is used for developing Java-based applications. It included JRE, debugging tool & some other libraries.

Moreover, there are two different java versions that you install OpenJDK & Oracle java.

OpenJDK installation

We will start by installing the java 8 on our systems first & then will also discuss other java versions also. Open terminal & enter the following command to install Java 8,

# yum install java-1.8.0-openjdk-devel

This will install JDK on the system, to only install JRE on the system, use

# yum install java-1.8.0-openjdk

Java 8 is still one of the most widely used java versions but if you are looking at the latest java version with long term support, then you should be using Java 11. Let’s learn how to install this on our system,

# yum install java-11-openjdk-devel

To install JRE on the system, the command is

# yum install java-11-openjdk

Oracle Java installation

Oracle java packages are not available for installation on operating system default repositories & can only be installed using the rpm packages that are available on the official website’s DOWNLOAD PAGE. Once you download the rpm package, then you can install it similarly as you would any other rpm package, either using yum command or rpm command,

# yum localinstall ORACLE_JAVA_PACKAGE.rpm

That’s it, java is now installed on the system. The next part is configuring the default java for the systems as you might have more than one java version installed on the system.

Configuring default Java

Command to configure the default java is,

# alternatives –config java

Then you should get the java versions installed on the system, type the number mentioned against the java version & press enter to make it the default versions. This will change the java versions to one that you want. Please do let us know if you have questions, queries or suggestions using the comment box below.

The post How to install Java on CentOS & RHEL appeared first on The Linux GURUS.