📧 Jenkins Email Notification and Build Triggers Guide

A simple, complete reference for configuring Jenkins triggers and email notifications — explained in easy words! 🚀

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🧩 Parameterized Jenkins Jobs

✅ What is a Parameterized Job?

A parameterized job allows users to input values when triggering a build. These inputs (parameters) are passed into the job to customize the behavior.

🧰 Common Parameter Types

Type	Description
📝 String	Text input (e.g., version number)
🔘 Boolean	Checkbox (true / false)
📋 Choice	Dropdown menu
🔐 Password	Secure hidden input
📄 Multi-line String	Multi-line text
📎 File	Upload a file
⚡ Active Choice 🔌	Dynamic options (via plugin)
🌿 Git Parameter 🔌	Pick Git branches/tags (via plugin)

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✍️ Example for Pipeline Jobs

pipeline {
  agent any
  parameters {
    string(name: 'VERSION', defaultValue: '1.0', description: 'Version to deploy')
    booleanParam(name: 'RUN_TESTS', defaultValue: true, description: 'Run tests?')
    choice(name: 'ENV', choices: ['dev', 'stage', 'prod'], description: 'Target environment')
  }
  stages {
    stage('Deploy') {
      steps {
        echo "Deploying version ${params.VERSION} to ${params.ENV}"
      }
    }
  }
}

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⏰ Jenkins Build Triggers – Explained Simply

Trigger	Meaning	Example Use Case
🌐 Trigger builds remotely	Run build via URL or script	Use curl to trigger Jenkins
🔗 Build after other projects are built	Trigger this job after another finishes	Chain builds
⏲️ Build periodically	Run on schedule (CRON)	Every day at 9 AM
🪝 GitHub hook trigger	GitHub sends signal to build	Webhook setup
🔄 Poll SCM	Jenkins checks Git for changes	Every 5 mins check for code changes

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📌 Example CRON: Build every 5 minutes

H/5 * * * *

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🔁 Jenkins Post-Build Triggers (Detailed)

Option	Description	Use Case
✅ Trigger only if build is stable	Run next job only if build is successful	Production deployment
⚠️ Trigger even if build is unstable	Continue even if tests fail	Notify, generate reports
❌ Trigger even if the build fails	Run next job on failure	Send alerts, collect logs
🔁 Always trigger (even if aborted)	Run regardless of result	Cleanup, release locks

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🚫 "Ignore post-commit hooks" in Jenkins

✅ What is a post-commit hook?

A Git or GitHub feature that sends a signal to Jenkins after code is pushed.

❓ What does "Ignore post-commit hooks" mean?

It means Jenkins will ignore webhook signals and won’t build the job automatically.

💡 When to use

• You only want Jenkins to poll Git (using Poll SCM)
• You don’t want automatic builds from webhooks

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📧 Jenkins Email Notification Setup

✅ What it does

Sends emails when a build fails, becomes unstable, or returns to normal.

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🛠️ Step 1: Configure Global Settings

Navigate to:

Manage Jenkins → Configure System → E-mail Notification

Set the following:

• 📮 SMTP server: smtp.gmail.com
• 🔌 SMTP port: 587
• 🔐 Use SMTP Auth: ✅
• 👤 Username: [email protected]
• 🔑 Password: App Password (not your Gmail password)
• 📨 From Address: [email protected] or your Gmail
• 🔒 TLS / SSL: Enable as required

✅ Click Test Configuration

Also set the System Admin e-mail address at the top.

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📬 Step 2: Add Email Notification to Job

1. Open your Jenkins job
2. Click Configure
3. Scroll to Post-build Actions
4. Click Add post-build action → E-mail Notification
5. Add recipients:

[email protected] [email protected]

Optional checkboxes:

• ☑️ Send email for every unstable build
• ☑️ Send separate e-mails to individuals who broke the build

Click Save

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❓ Will Jenkins send email to [email protected]?

✅ Yes, if:

• SMTP is properly configured
• The email address is valid
• The build fails or becomes unstable

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📤 From which email will Jenkins send?

From the email set in:

Manage Jenkins → Configure System → E-mail Notification → From address

Usually:

[email protected]

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🧾 Summary: Jenkins Notifications & Triggers

Feature	Purpose
🎛️ Parameterized Jobs	Let users customize job input
🚀 Triggers	Auto-start job on events (push, schedule, scripts)
🔁 Post-build Triggers	Control what happens after job finishes
📧 Email Notification	Send emails on failure / unstable / stable
🚫 Ignore post-commit hooks	Prevent auto-builds from GitHub/Git

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🧠 Pro Tip

Always test email configuration using the "Test configuration by sending test e-mail" button in Jenkins settings! ✅

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