Jenkins: Install with Docker and Create Your First Pipeline

Step 1: Check the requirements

Current Jenkins LTS releases need Java 21 or 25, and Java 17 is no longer supported. The official Docker images bundle the right Java, so using the jenkins/jenkins LTS image with a JDK 21 tag avoids setting up Java yourself. Always check the Jenkins documentation for the current LTS version and Java support.

Step 2: Run Jenkins in Docker

This starts the LTS image with its data in a named volume, so your jobs and settings survive restarts. Port 8080 serves the web interface, and port 50000 is only for inbound build agents, so you can omit it on a single machine. This simple setup is fine for learning; building Docker images from inside Jenkins needs extra setup described in the official documentation.

docker run -d --name jenkins \
  --restart=on-failure \
  -p 8080:8080 -p 50000:50000 \
  -v jenkins_home:/var/jenkins_home \
  jenkins/jenkins:lts-jdk21

Step 3: Unlock Jenkins

Open http://localhost:8080. The Unlock Jenkins page asks for an administrator password that Jenkins generated on first start. Find it in the container's logs, between rows of asterisks, or read it from the data folder, then paste it into the Administrator password box and click Continue.

docker logs jenkins

# or:
docker exec jenkins cat /var/jenkins_home/secrets/initialAdminPassword

Step 4: Finish the setup wizard

On the Customize Jenkins page, choose Install suggested plugins, which installs a sensible default set. Then create your first admin user and click Save and Finish, and then Start using Jenkins. Manage plugins later under Manage Jenkins, then Plugins, and keep them updated, since plugins are a common source of security fixes.

Step 5: Create and run a pipeline job

Click New Item, enter a name, choose Pipeline, and click OK. In the Pipeline section, set Definition to Pipeline script and paste a Jenkinsfile. Save, then click Build Now. Open the build in Build History and choose Console Output to read the log.

pipeline {
    agent any
    stages {
        stage('Build') {
            steps {
                echo 'Building...'
            }
        }
        stage('Test') {
            steps {
                echo 'Testing...'
            }
        }
    }
}