🚀 Jenkins CI/CD Automation Server Installation on AlmaLinux

Ready to supercharge your development workflow? 🎯 Jenkins is the most popular automation server that helps teams build, test, and deploy code automatically! In this guide, we’ll set up Jenkins on AlmaLinux and create your first CI/CD pipeline. Let’s turn your manual deployment headaches into automated magic! ✨

🤔 Why is Jenkins Important?

Jenkins transforms how development teams work by automating everything! 🎪 Here’s why millions of developers love it:

• ⚡ Automated Builds: Code changes trigger automatic builds and tests
• 🔄 Continuous Integration: Catch bugs early with automatic testing
• 🚀 Fast Deployments: Deploy to production with one click
• 📊 Team Collaboration: Everyone sees build status and results
• 🛡️ Quality Control: Prevent broken code from reaching production
• 💰 Save Time & Money: Reduce manual work and human errors
• 🌍 Works Everywhere: Deploy to any server or cloud platform

Think of Jenkins as your personal DevOps assistant that never sleeps! 🤖

🎯 What You Need

Let’s make sure you’re ready for Jenkins installation! ✅

• ✅ AlmaLinux 8 or 9 server with internet connection
• ✅ At least 2GB RAM (4GB recommended for better performance)
• ✅ 10GB free disk space (more for large projects)
• ✅ sudo privileges on your system
• ✅ Basic knowledge of Linux command line
• ✅ Java 11 or 17 (we’ll install this together!)
• ✅ Web browser to access Jenkins interface
• ✅ 15 minutes of your time and enthusiasm! 🎉

Don’t worry if you’re new to this - we’ll explain every step! 🌟

📝 Step 1: Prepare Your System

First, let’s get your AlmaLinux system ready for Jenkins! 🎯

# Update your system packages
sudo dnf update -y

# Install essential development tools
sudo dnf groupinstall -y "Development Tools"

# Install curl and wget for downloading files
sudo dnf install -y curl wget

Great job! 🎉 Your system is now prepared for Jenkins installation.

🔧 Step 2: Install Java (Required for Jenkins)

Jenkins needs Java to run. Let’s install OpenJDK 17! ☕

# Install OpenJDK 17 (recommended for Jenkins)
sudo dnf install -y java-17-openjdk java-17-openjdk-devel

# Verify Java installation
java -version

# Set JAVA_HOME environment variable
echo 'export JAVA_HOME=/usr/lib/jvm/java-17-openjdk' | sudo tee -a /etc/environment
source /etc/environment

# Check JAVA_HOME is set correctly
echo $JAVA_HOME

Expected Output:

openjdk version "17.0.8" 2023-07-18
OpenJDK Runtime Environment (build 17.0.8+7-RPM-1)

Perfect! ✅ Java is ready for Jenkins!

🌟 Step 3: Add Jenkins Repository

Let’s add the official Jenkins repository to get the latest version! 📦

# Download and add Jenkins repository key
sudo wget -O /etc/yum.repos.d/jenkins.repo https://pkg.jenkins.io/redhat-stable/jenkins.repo

# Import Jenkins GPG key for security
sudo rpm --import https://pkg.jenkins.io/redhat-stable/jenkins.io-2023.key

# Update package cache with new repository
sudo dnf update -y

Excellent! 🎯 Now we can install Jenkins from the official repository.

✅ Step 4: Install Jenkins

Time to install the star of the show - Jenkins! 🌟

# Install Jenkins automation server
sudo dnf install -y jenkins

# Start Jenkins service
sudo systemctl start jenkins

# Enable Jenkins to start automatically on boot
sudo systemctl enable jenkins

# Check Jenkins service status
sudo systemctl status jenkins

Expected Output:

● jenkins.service - Jenkins Continuous Integration Server
   Loaded: loaded (/usr/lib/systemd/system/jenkins.service; enabled)
   Active: active (running) since Mon 2025-09-14 10:00:00 UTC

Amazing! 🎉 Jenkins is now running on your server!

🔧 Step 5: Configure Firewall

Let’s open the firewall so you can access Jenkins from your web browser! 🌐

# Open port 8080 for Jenkins web interface
sudo firewall-cmd --permanent --add-port=8080/tcp

# Reload firewall rules
sudo firewall-cmd --reload

# Verify port is open
sudo firewall-cmd --list-ports

Perfect! 🔓 Jenkins is now accessible from the web.

🌟 Step 6: Access Jenkins Web Interface

Time for the exciting part - accessing Jenkins! 🎯

1. Open your web browser 🌐
2. Navigate to: http://your-server-ip:8080
3. You’ll see the Jenkins unlock screen 🔐

Get the initial admin password:

# Display the initial admin password
sudo cat /var/lib/jenkins/secrets/initialAdminPassword

Copy this password - you’ll need it for the setup wizard! 📝

✅ Step 7: Complete Jenkins Setup Wizard

Follow these steps in your web browser: 🎭

1. Paste the admin password and click “Continue”
2. Choose “Install suggested plugins” (easiest option for beginners)
3. Wait for plugins to install (grab a coffee! ☕)
4. Create your first admin user:
   • Username: admin
   • Password: YourSecurePassword123!
   • Full Name: Your Name
   • Email: [email protected]
5. Configure Jenkins URL (usually auto-detected)
6. Click “Start using Jenkins” 🚀

Congratulations! 🎉 Jenkins is ready to automate your projects!

🎮 Quick Examples

Let’s create some practical Jenkins automation examples! 🎯

Example 1: Simple “Hello World” Job

# In Jenkins web interface:
# 1. Click "New Item"
# 2. Name: "hello-world"
# 3. Select "Freestyle project"
# 4. In Build section, add "Execute shell":

echo "🎉 Hello from Jenkins automation!"
echo "Build started at: $(date)"
echo "Running on server: $(hostname)"
echo "✅ Automation is working perfectly!"

Example 2: Git Repository Build

# Create a job that builds from Git:
# 1. New Item → "git-build" → Freestyle project
# 2. Source Code Management → Git
# 3. Repository URL: https://github.com/username/project.git
# 4. Build section → Execute shell:

echo "🔄 Starting build from Git repository..."
ls -la
echo "📦 Installing dependencies..."
# npm install  # For Node.js projects
# mvn compile  # For Java projects
echo "🧪 Running tests..."
# npm test     # For Node.js projects
echo "✅ Build completed successfully!"

Example 3: Automated Deployment Pipeline

# Advanced pipeline with multiple stages:
#!/bin/bash

echo "🚀 Starting deployment pipeline..."

# Stage 1: Code Quality Check
echo "📊 Checking code quality..."
# Run linting, security scans

# Stage 2: Build Application
echo "🔧 Building application..."
# Compile code, create artifacts

# Stage 3: Run Tests
echo "🧪 Running comprehensive tests..."
# Unit tests, integration tests

# Stage 4: Deploy to Staging
echo "🎭 Deploying to staging environment..."
# Deploy to test server

# Stage 5: Production Deployment
echo "🌍 Deploying to production..."
# Deploy to live server

echo "✅ Pipeline completed successfully!"

🚨 Fix Common Problems

Running into issues? Don’t worry - let’s fix them together! 🔧

Problem 1: Jenkins Won’t Start

Symptoms: systemctl status jenkins shows failed status

Solution:

# Check Java installation
java -version

# Check Jenkins logs
sudo journalctl -u jenkins -f

# Fix permissions if needed
sudo chown -R jenkins:jenkins /var/lib/jenkins

# Restart Jenkins
sudo systemctl restart jenkins

Problem 2: Can’t Access Web Interface

Symptoms: Browser can’t connect to Jenkins

Solution:

# Check if Jenkins is running
sudo systemctl status jenkins

# Verify port 8080 is open
sudo ss -tlnp | grep 8080

# Check firewall settings
sudo firewall-cmd --list-ports

# Restart firewall if needed
sudo systemctl restart firewalld

Problem 3: “Permission Denied” Errors

Symptoms: Jobs fail with permission errors

Solution:

# Add jenkins user to necessary groups
sudo usermod -a -G docker jenkins  # For Docker builds
sudo usermod -a -G wheel jenkins   # For sudo access

# Fix Jenkins home directory permissions
sudo chown -R jenkins:jenkins /var/lib/jenkins

# Restart Jenkins to apply changes
sudo systemctl restart jenkins

Problem 4: Out of Memory Errors

Symptoms: Jenkins becomes slow or crashes

Solution:

# Edit Jenkins configuration
sudo nano /etc/sysconfig/jenkins

# Increase memory settings
JENKINS_JAVA_OPTIONS="-Xmx2048m -XX:MaxPermSize=512m"

# Restart Jenkins
sudo systemctl restart jenkins

📋 Simple Commands Summary

Here’s your Jenkins command cheat sheet! 📚

💡 Tips for Success

Make your Jenkins journey smooth with these pro tips! 🌟

• 🔐 Security First: Always use strong passwords and enable security features
• 🔄 Regular Backups: Backup your Jenkins configuration weekly
• 📊 Monitor Resources: Keep an eye on CPU and memory usage
• 🎯 Start Simple: Begin with basic jobs before complex pipelines
• 📚 Learn Gradually: Master one feature at a time
• 🤝 Team Training: Ensure your team knows how to use Jenkins
• 🔧 Plugin Management: Only install plugins you actually need
• 📝 Document Everything: Keep notes about your pipeline configurations
• 🧪 Test Thoroughly: Always test changes in staging first
• 🚀 Automate Everything: If you do it twice, automate it!

🏆 What You Learned

Look at everything you’ve accomplished! 🎉

• ✅ Installed Jenkins automation server on AlmaLinux
• ✅ Configured Java environment for optimal performance
• ✅ Set up firewall rules for secure web access
• ✅ Completed setup wizard and created admin account
• ✅ Created your first job with automated builds
• ✅ Built Git integration for continuous integration
• ✅ Mastered troubleshooting common Jenkins issues
• ✅ Learned best practices for production deployments
• ✅ Gained DevOps skills that employers highly value
• ✅ Automated manual tasks to save time and reduce errors

You’re now a Jenkins automation expert! 🌟

🎯 Why This Matters

Your Jenkins skills open amazing opportunities! 🚀

For Your Career:

• 💼 DevOps engineers with Jenkins skills earn 25% more
• 🎯 Companies desperately need automation experts
• 🌟 Jenkins experience leads to senior developer roles
• 🤝 You can help teams deliver software faster

For Your Projects:

• ⚡ Deploy code changes in minutes, not hours
• 🛡️ Catch bugs before customers see them
• 📊 Get instant feedback on code quality
• 🎉 Focus on coding instead of manual deployment

For Your Team:

• 🚀 Increase deployment frequency by 10x
• 🔧 Reduce deployment failures by 50%
• 😊 Happier developers with less manual work
• 💰 Save thousands in operational costs

You’ve just learned one of the most valuable DevOps skills! 🏆

Remember, every expert was once a beginner. You took the first step toward mastering CI/CD automation, and that’s something to be proud of! Keep experimenting, keep learning, and soon you’ll be building complex deployment pipelines like a pro! ⭐

Happy automating! 🙌