Introduction:

In today’s fast-paced software development world, DevOps plays a critical role in automating the build, test, and deployment process. In this blog, I’ll walk you through a complete end-to-end CI/CD pipeline I built using Jenkins on AWS EC2, integrating popular DevOps tools like Git, Maven, SonarQube, Nexus, and Tomcat. This hands-on project not only helped me understand how each tool fits into the software development lifecycle but also gave me real-world experience in deploying a robust and scalable automation pipeline. Whether you're a DevOps beginner or someone brushing up on core concepts, this post will give you a practical view of setting up your own pipeline from scratch.

Tech Stack:

Git: Source code management
Maven: Build tool
SonarQube: Code quality check
Nexus: Artifact storage
Tomcat: Webserver for deployment
Jenkins: CI/CD pipeline
AWS EC2: Hosting all services

Step-by-Step Process to Deploy the Application:

STEP-1: LAUNCH 4 INSTANCES WITH SAME PEM FILE
JENKINS: T2.MICRO
TOMCAT: T2.MICRO
SONAR: T2.MEDIUM (25 GB OF EBS VOLUME)
NEXUS: T2.MEDIUM (25 GB OF EBS VOLUME)

SETUP SERVICES IN THEIR RESPECTIVE SERVERS

STEP-2: refer the below scripts to install Jenkins, Tomcat ,Sonar and Nexus on respective servers.

Jenkins Script

  #STEP-1: INSTALLING GIT
  yum install git -y

  #STEP-2: GETTING THE REPO (jenkins.io --> download --> redhat)
  sudo wget -O /etc/yum.repos.d/jenkins.repo \
      https://pkg.jenkins.io/redhat-stable/jenkins.repo
  sudo rpm --import https://pkg.jenkins.io/redhat-stable/jenkins.io-2023.key
  sudo yum upgrade
  # Add required dependencies for the jenkins package
  sudo yum install fontconfig java-21-openjdk
  sudo yum install jenkins
  sudo systemctl daemon-reload

  #STEP-3: DOWNLOAD JAVA17 AND JENKINS
  yum install java-17-amazon-corretto -y
  yum install jenkins -y

  #STEP-4: RESTARTING JENKINS
  systemctl start jenkins.service
  systemctl status jenkins.service

Tomcat Script:

  #STEP-1: INSTALL JAVA 17
  yum install java-17-amazon-corretto -y

  #STEP-2: DOWNLOAD & EXTRACT TOMCAT
  wget https://downloads.apache.org/tomcat/tomcat-9/v9.0.104/bin/apache-tomcat-9.0.104.tar.gz
  tar -zxvf apache-tomcat-9.0.104.tar.gz

  #STEP-3: CONFIGURE TOMCAT USERS (GUI & SCRIPT ACCESS)
  sed -i '56  a\<role rolename="manager-gui"/>' conf/tomcat-users.xml
  sed -i '57  a\<role rolename="manager-script"/>' conf/tomcat-users.xml
  sed -i '58  a\<user username="tomcat" password="admin@123" roles="manager-gui, manager-script"/>' conf/tomcat-users.xml
  sed -i '59  a\</tomcat-users>' conf/tomcat-users.xml
  sed -i '56d' conf/tomcat-users.xml
  #STEP-4: REMOVE IP RESTRICTIONS FOR MANAGER ACCESS
  sed -i '21d' webapps/manager/META-INF/context.xml
  sed -i '22d' webapps/manager/META-INF/context.xml

  #STEP-5: START TOMCAT SERVER
  sh bin/startup.sh

Nexus Script:

  #STEP-1: INSTALL JAVA 17
  yum install java-17-amazon-corretto -y

  #STEP-2: DOWNLOAD NEXUS AND EXTRACT
  cd /opt
  wget https://download.sonatype.com/nexus/3/nexus-unix-x86-64-3.79.0-09.tar.gz
  tar -zxvf nexus-unix-x86-64-3.79.0-09.tar.gz

  #STEP-3: CREATE NEXUS USER & SET PERMISSIONS
  useradd nexus
  vim /opt/nexus-3.79.0-09/bin/nexus
  # (Edit the file and set) run_as_user="nexus"

  #STEP-4: SWITCH TO NEXUS USER AND START SERVICE
  su - nexus
  /opt/nexus-3.79.0-09/bin/nexus start
  /opt/nexus-3.79.0-09/bin/nexus status

  #STEP-5: VERIFY NEXUS IS RUNNING
  ps -ef | grep nexus
  ss -tuln | grep 8081

  #STEP-6: GET DEFAULT ADMIN PASSWORD
  cat /opt/sonatype-work/nexus3/admin.password

Sonar Setup:

  #STEP-1: INSTALL JAVA OPENJDK 11
  amazon-linux-extras install java-openjdk11 -y

  #STEP-2: DOWNLOAD SONARQUBE
  cd /opt/
  wget https://binaries.sonarsource.com/Distribution/sonarqube/sonarqube-8.9.6.50800.zip

  #STEP-3: UNZIP AND CONFIGURE PERMISSIONS
  unzip sonarqube-8.9.6.50800.zip
  useradd sonar
  chown sonar:sonar sonarqube-8.9.6.50800 -R

  #STEP-4: SWITCH TO SONAR USER AND START SONARQUBE
  su - sonar
  cd /opt/sonarqube-8.9.6.50800/bin/linux-x86-64/
  sh sonar.sh start
  sh sonar.sh status

Go to http://<your-ip>:8080 and log in to Jenkins.
Go to Manage Jenkins → Plugin Manager → Available
Install these plugins:

SonarQube Scanner – for code scanning

Nexus Artifact Uploader – to upload files to Nexus

SSH Agent – to send files to another server.

STEP-4:Create a Jenkins pipeline job and write a Jenkins file for deploy a web application, usually we have 2 types of pipelines,

scripted ,declarative

Here i am using scripted pipeline for the Jenkins file

STAGE-1 : GET THE CODE FROM GITHUB TO CI-SERVER
node { stage("Code") { git "https://github.com/PasupuletiBhavya/one.git" } }
STAGE-2 : BUILD THE SOURCE CODE: GO TO MANAGE JENKINS >> GLOBAL TOOL CONFIGURATION >> MAVEN ADD INSTALLER WITH THE NAME OF maven WITH VERISON (3.9.9)
stage("Build") { def mavenHome = tool name: "maven3", type: "maven" def mavenCMD = "${mavenHome}/bin/mvn" sh "${mavenCMD} clean package" }
CHECK THE WAR FILE IN JENKINS FOR CONFIRMATION AFTER SUCCESSFULL BUILD

STAGE-3 : SCAN THE SOURCE CODE: LOGIN INTO SONAR GO TO MY ACCOUNT >> SECURITY >> ENTER A TOKEN NAME AND GENERATE A TOKEN

NOW INTEGRATE THE SONAR TO JENKINS MANAGE JENKINS >> CONFIGURE SYSTEM >> SONAR SERVER

stage("CQA") { withSonarQubeEnv('mysonar') { def mavenHome = tool name: "maven3", type: "maven" def mavenCMD = "${mavenHome}/bin/mvn" sh "${mavenCMD} sonar:sonar" } }
AFTER SUCCESSFULL BUILD CHECK FOR ANY BUGS IN THE SONARQUBE DASHBOARD>PROJECTS

STAGE-4: Upload WAR File to Nexus Artifactory

Create a new repository in Nexus:
• Name: bhavya-repo
• Format: maven2 (hosted)
• Version Policy: Releases
• Deployment Policy: Allow Redeploy

Install the Nexus Artifact Uploader plugin in Jenkins.

Go to Jenkins → Pipeline Syntax, choose Nexus Artifact Uploader from the dropdown.

Fill in the required fields:
• Nexus URL
• Repository name (bhavya-repo)
• Group ID, Artifact ID, Version(You can find in the pom.xml file)
• Path to WAR file

Click Generate Pipeline Script and add it to your Jenkinsfile

    stage("Nexus") {
        nexusArtifactUploader artifacts: [[
            artifactId: 'myweb', 
            classifier: '', 
            file: 'target/myweb-8.6.9.war', 
            type: 'war'
        ]],
        credentialsId: 'nexus',
        groupId: 'in.javahome',
        nexusUrl: '34.229.123.124:8081',
        nexusVersion: 'nexus3',
        protocol: 'http',
        repository: 'bhavya-repo',
        version: '8.6.9'
    }

AFTER SUCESSFULL BIULD YOU CAN SEE THE WAR FILES UPLOADED IN NEXUS

STAGE-5 : DEPLOY THE APPLICATION INTO TOMCAT WEB SERVER:

(Put your pem file privte key)

    #!/bin/bash

    # Move Tomcat folder to ec2-user home
    mv apache-tomcat-9.0.104 /home/ec2-user/

    # Change ownership to ec2-user
    chown ec2-user:ec2-user /home/ec2-user/apache-tomcat-9.0.104 -R

    # Switch to tomcat directory
    cd /home/ec2-user/apache-tomcat-9.0.104/bin

    # Stop Tomcat if running
    ./shutdown.sh

    # Start Tomcat
    ./startup.sh

    # Navigate to webapps folder
    cd ../webapps
    pwd

    stage("Deployment") {
        sshagent(['8bce0b0e-c5db-4aac-bf07-4831ca13a760']) {
            sh 'scp -o StrictHostKeyChecking=no target/*.war ec2-user@52.23.240.218:/home/ec2-user/apache-tomcat-9.0.104/webapps/'
        }
    }

AFTER SUCCESSFULL BUILD YOU CAN SEE YOUR WAR FILED DEPLOYED INTO TOMCAT SERVER

CLICK ON YOUR WAR FILE TO VIEW YOUR APPLICATION

Final Pipeline Flow Summary

From Code to Deployment:

Developer pushes code to Git
Jenkins job triggers → SonarQube analysis
Maven builds code → Nexus stores WAR file
Jenkins deploys to Tomcat → Application is live

✅ What I Learned

How each DevOps tool works in real-world projects.
Jenkins integration with multiple tools for continuous integration and delivery.
Managing AWS instances and implementing security best practices.
Debugging and automating deployment steps to enhance workflow efficiency.

🔗 Resources & Links

📁 https://github.com/PasupuletiBhavya
🖥️ Tool Sites:
- Jenkins
- SonarQube
- Nexus
- Apache Tomcat

This hands-on project provided me with a deeper understanding of DevOps pipelines and toolchains. For anyone just starting with DevOps, building a project like this is an invaluable way to learn and get practical experience. It also makes a great addition to your resume!If this article added value to your journey, your support would mean the world to me — only if it's within your means. Let's stay connected on LinkedIn. Thank you for reading, and let's keep growing together! 💕

💬 Feel free to connect or comment if you have questions or want to collaborate!

End-to-End CI/CD Pipeline with Jenkins on AWS

Introduction:

Step-by-Step Process to Deploy the Application:

Final Pipeline Flow Summary

✅ What I Learned

🔗 Resources & Links

Subscribe to my newsletter

Bhavya Pasupuleti

Bhavya Pasupuleti

End-to-End CI/CD Pipeline with Jenkins on AWS

Introduction:

Step-by-Step Process to Deploy the Application:

STEP-3: Login to Jenkins & Install Plugins

Final Pipeline Flow Summary

✅ What I Learned

🔗 Resources & Links

Subscribe to my newsletter

Bhavya Pasupuleti

Bhavya Pasupuleti