Install Jenkins – Ubuntu, CentOS

What is Jenkins? Jenkins is a well-known open source CI/CD (Continuous Integration and Continuous Delivery) automation server written in Java.

In this tutorial i will show how to install Jenkins on Ubuntu-18.04, 16.04 and Centos-7, 6 and how to perform initial Jenkins configuration.

Jenkins requires Java, so firstly it needs to install OpenJDK-8 JRE/JDK (Java Runtime Environment and Java Development Kit).

Install Java

Jenkins requires Java and if it is not installed you may receive an error as follows:

ERROR: No Java executable found in current PATH: /bin:/usr/bin:/sbin:/usr/sbin

Found an Incorrect Java Version? Modern versions of Jenkins require Java 8 and it is the ONLY supported runtime environment.

Check if Java is installed and what is the version:

$ java -version

Install OpenJDK-8 JRE/JDK on Ubuntu:

$ sudo apt-get update
$ sudo apt-get install openjdk-8-jdk openjdk-8-jre

Install OpenJDK-8 JRE/JDK on CentOS:

$ sudo yum install java-1.8.0-openjdk java-1.8.0-openjdk-devel

Install Jenkins on Ubuntu

Install the latest stable Jenkins version on Ubuntu:

$ wget -q -O - https://pkg.jenkins.io/debian/jenkins-ci.org.key | sudo apt-key add -
$ sudo sh -c 'echo deb http://pkg.jenkins.io/debian-stable binary/ > /etc/apt/sources.list.d/jenkins.list'
$ sudo apt-get update
$ sudo apt-get install jenkins

As only Jenkins is installed on Ubuntu, it will be started and added to auto-start automatically.

Install Jenkins on CentOS

Install the latest stable Jenkins version on CentOS:

$ sudo curl -o /etc/yum.repos.d/jenkins.repo http://pkg.jenkins-ci.org/redhat-stable/jenkins.repo 
$ sudo rpm --import https://jenkins-ci.org/redhat/jenkins-ci.org.key
$ sudo yum install jenkins

On CentOS, Jenkins is configured to start on boot automatically, but by default it is stopped.

To start the Jenkins, run:

$ sudo service jenkins start

Configure Jenkins

By default, Jenkins listens on port 8080.

Open http://$JENKINS_IP:8080 in your web-browser to start configuration.

To unlock Jenkins and sign in it will be required to copy and paste the password that has been written to the file /var/lib/jenkins/secrets/initialAdminPassword on Jenkins server.

$ sudo cat /var/lib/jenkins/secrets/initialAdminPassword
ea0e27bb08cd497c86a3777121c8b967

After unlocking Jenkins, select plugins to install, create administrative user and configure URL that will be used to access Jenkins.

Now you are ready to start using Jenkins!

Recommended Book
devops

This is a must-read for anyone who wants to understand, explain and implement DevOps culture, process and tools for high performance development and operations.

All DevOps practices in a single place - organisational, cultural and technical. Lots of exceptional case studies.

Increase profitability, elevate work culture, and exceed productivity goals through DevOps practices.