Jenkins Plugins: Installing and Managing

Plugins are add-ons that give Jenkins new abilities. Out of the box, Jenkins is a basic automation server. Plugins turn it into a powerful tool that connects with Git, Docker, Slack, AWS, test frameworks, and hundreds of other systems.

Think of Jenkins as a smartphone. The phone does very little on its own. You install apps to add features — a camera app, a maps app, a banking app. Jenkins plugins work exactly the same way.

Why Plugins Exist

Jenkins was designed to be lightweight at its core. Instead of building every possible feature into the main application, the team created a plugin system. This keeps Jenkins fast and lets you install only what your project needs.

There are over 1,800 plugins available in the Jenkins Plugin Index. Categories include source control, build tools, testing, deployment, notifications, and security.

How to Install a Plugin

Jenkins provides two ways to install plugins: through the web interface and via the command line.

Method 1: Install via Dashboard (Most Common)

Step 1: Go to Dashboard
Step 2: Click "Manage Jenkins"
Step 3: Click "Manage Plugins"
        (or "Plugins" in newer Jenkins versions)
Step 4: Click the "Available plugins" tab
Step 5: Search for the plugin name
Step 6: Check the box next to the plugin
Step 7: Click "Install without restart"
        OR
        "Download now and install after restart"

Method 2: Upload a Plugin File (.hpi or .jpi)

Some organizations do not allow Jenkins to access the internet directly. In this case, you download the plugin file from the Jenkins website on another machine, transfer the file, and upload it manually.

Manage Jenkins → Plugins → Advanced → Deploy Plugin
→ Upload the .hpi file
→ Jenkins installs it

Plugin Manager Tabs Explained

Essential Plugins for Every Jenkins Setup

These plugins cover the most common needs and are recommended for most teams.

Essential Plugin List

SOURCE CONTROL
├── Git Plugin           → Connect Jenkins to Git repositories
└── GitHub Integration   → React to GitHub pull requests and pushes

BUILD TOOLS
├── Maven Integration    → Build Java projects with Maven
├── NodeJS Plugin        → Run Node.js scripts in builds
└── Gradle Plugin        → Build Android and Java projects

PIPELINES
├── Pipeline             → Create Pipeline jobs
└── Blue Ocean           → Modern visual interface for pipelines

NOTIFICATIONS
├── Email Extension      → Send detailed build emails
├── Slack Notification   → Post build results to Slack channels
└── MS Teams Notifier    → Post results to Microsoft Teams

TESTING AND QUALITY
├── JUnit Plugin         → Publish test results in Jenkins
└── Cobertura Plugin     → Show code coverage reports

DEPLOYMENT
├── SSH Agent            → Connect to remote servers with SSH
└── Kubernetes Plugin    → Run build agents on Kubernetes

Updating Plugins

Outdated plugins can cause security problems or break compatibility with newer Jenkins versions. Make a habit of checking for updates regularly.

Manage Jenkins → Plugins → Updates tab
→ Select plugins to update
→ Click "Download now and install after restart"
→ After update, restart Jenkins from:
  http://your-jenkins:8080/restart

Always read the plugin's changelog before updating in a production environment. Some updates change behavior and require configuration adjustments.

Uninstalling a Plugin

Remove plugins you no longer need. Unused plugins slow down Jenkins startup and may create security risks.

Manage Jenkins → Plugins → Installed plugins
→ Find the plugin
→ Click "Uninstall"
→ Restart Jenkins to complete removal

Jenkins warns you if other plugins depend on the one you are removing. Never uninstall a plugin that others rely on without first removing those dependent plugins.

Plugin Dependencies Explained

Some plugins require other plugins to work. For example, the Pipeline Stage View plugin requires the Pipeline plugin. When you install a plugin, Jenkins automatically installs its dependencies.

Diagram: Plugin Dependency Chain

  Blue Ocean Plugin
        |
        ↓ requires
  Pipeline Plugin
        |
        ↓ requires
  Git Plugin
        |
        ↓ requires
  Git Client Plugin

When you install Blue Ocean, Jenkins installs all four plugins in the chain automatically.

Pinning a Plugin

Pinning keeps a plugin at a specific version and prevents Jenkins from updating it automatically. Use this when an update breaks something and you need time to fix the issue before upgrading again.

Key Points

• Plugins add features to Jenkins. Install only what your project needs.
• Install plugins from the dashboard: Manage Jenkins → Plugins → Available plugins.
• Keep plugins updated to avoid security issues and compatibility problems.
• When you install a plugin, Jenkins automatically installs its dependencies.
• Remove unused plugins to keep Jenkins lean and secure.