Tools Used

GitHub – To host the application code

• Jenkins – To automate the build and deployment

• Maven – For build and packaging

• Apache Tomcat – For deploying the Java application

• Amazon EC2 – As the hosting server for everything

🔗 Step-by-Step Workflow

1️⃣ Code on GitHub

Your application code lives in a GitHub repository. Whenever you push changes to the repository, it should automatically trigger the Jenkins job.

2️⃣ Jenkins Pulls the Code

Inside Jenkins, configure the job to:

• Use GitHub hook trigger for GITScm polling

• Pull code from your GitHub repository whenever there’s a new push

Make sure to set up a webhook in GitHub pointing to your Jenkins server.

3️⃣ Configure Maven Goals in Jenkins

In the Jenkins job:

• Under Build, specify Maven goals like:

clean package- This compiles the code, runs tests, and packages the output (typically a .war file).

4️⃣ Deploy to Tomcat with Plugin

Install the Jenkins plugin:

Deploy to Container

This plugin allows Jenkins to deploy the generated .war file to a Tomcat server.

Configure it in Post-build Actions:

• Specify Tomcat URL

• Set Tomcat username/password

• Path to .war file

5️⃣ All on Same EC2 Instance

Both Jenkins and Tomcat are installed on the same EC2 instance.

5️⃣ All on Same EC2 Instance

Both Jenkins and Tomcat are installed on the same EC2 instance.

6️⃣ Tomcat Port Change

By default, Jenkins and Tomcat both use port 8080. To avoid port conflict, we changed Tomcat’s port to 9080.

You can do this by editing server.xml in the Tomcat conf directory:

<Connector port="9080" protocol="HTTP/1.1" ... />

✅ CI/CD in Action

Here’s how it all ties together:

• You push code to GitHub

• GitHub sends a webhook trigger to Jenkins

• Jenkins pulls the latest code

• Jenkins runs Maven to build the app

• Jenkins deploys the .war file to Tomcat via post-build action

• App is now live on the EC2 instance (via Tomcat on port 9080)