1. Basic Jenkins Commands

• Start Jenkins:

    sudo service jenkins start
  

• Stop Jenkins:

    sudo service jenkins stop
  

• Restart Jenkins:

    sudo service jenkins restart
  

2. Jenkinsfile Basics

• Declarative Pipeline Syntax:

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

• Scripted Pipeline Syntax:

    node {
        stage('Build') {
            sh 'mvn clean install'
        }
        stage('Test') {
            sh 'mvn test'
        }
        stage('Deploy') {
            sh 'deploy.sh'
        }
    }
  

3. Key Pipeline Features

• Parallel Stages:

    stage('Parallel Tests') {
        parallel {
            stage('Unit Tests') {
                steps { echo 'Running unit tests...' }
            }
            stage('Integration Tests') {
                steps { echo 'Running integration tests...' }
            }
        }
    }
  

• Post Actions:

    post {
        success {
            echo 'Build succeeded'
        }
        failure {
            echo 'Build failed'
        }
    }
  

4. Environment Variables

• Defining Environment Variables:

    environment {
        APP_VERSION = '1.0.0'
    }
  

• Using Environment Variables:

    echo "Deploying version ${APP_VERSION}"
  

5. Jenkins CLI Commands

• Install Plugin:

    java -jar jenkins-cli.jar -s http://your_jenkins_url/ install-plugin plugin-name
  

• Restart Jenkins via CLI:

    java -jar jenkins-cli.jar -s http://your_jenkins_url/ safe-restart
  

6. Triggering Builds

• Manual Trigger: Click Build Now in the Jenkins UI.

• Git Trigger: Set up webhooks in GitHub/Bitbucket to trigger builds on code pushes.

7. Common Jenkinsfile Conditions

• Branch Condition:

    stage('Deploy to Prod') {
        when {
            branch 'main'
        }
        steps {
            echo 'Deploying to production'
        }
    }
  

8. Jenkins Blue Ocean

• Install Blue Ocean: Navigate to Manage Jenkins > Manage Plugins and install Blue Ocean for a modern UI.

9. Jenkins Plugins

• Key Plugins:

  • Git: For source control integration.

  • Docker: To build and run Docker containers.

  • Pipeline: For defining Jenkins pipelines as code.

  • Credentials Binding: For securely handling secrets.

10. Backup Jenkins

• Backup Configurations: Backup /var/lib/jenkins directory for all job configurations, plugins, and settings.