Welcome to Day 22 of the #90DaysOfDevOps challenge. Today, we will explore Jenkins, a popular open-source automation server. Jenkins is widely used for continuous integration and continuous delivery (CI/CD) pipelines, making it an essential tool for DevOps engineers. Let's dive in and discover the power of Jenkins.

What is Jenkins?

Jenkins is an extensible automation server that helps automate various aspects of software development processes. It provides a wide range of plugins and integrations, making it highly customizable and suitable for different project requirements. Jenkins is written in Java and runs on various platforms, including Windows, macOS, and Linux.

Jenkins enables the automation of repetitive tasks, such as building, testing, and deploying applications. It integrates with version control systems, build tools, and testing frameworks, allowing developers to streamline their workflows and improve collaboration.

With Jenkins, you can create pipelines to define the steps required to build, test, and deploy your applications. These pipelines can be configured using a domain-specific language called Groovy or through the Jenkins graphical interface.

Task: Creating a Freestyle Pipeline to Print "Hello World!"

In this task, we will create a simple freestyle pipeline in Jenkins to print the classic "Hello World!" message. Follow these steps:

1. Log in to your Jenkins instance. In my case, I'm using AWS so we need to take the Public IPv4 address and use the port 8080:

   

2. Click on "New Item" to create a new project.

   

3. Enter a name for your project (e.g., "HelloWorldPipeline") and select "Freestyle project" as the project type.

   

4. In the configuration page, scroll down to the "Build" section and click on "Add build step."

5. Choose "Execute shell" from the options.

6. In the command box, enter the following command: echo "Hello World!"

   

7. Apply and save your configuration.

8. Select Build Now to run the job and we will see the green mark to reflect it has been successfully executed.

   

9. We can see the output by clicking on the Build #1 icon and moving to Console Output:

   

Now, you have successfully created a freestyle pipeline in Jenkins. When you run this pipeline, it will execute the "echo" command and print "Hello World!" as the output.

Feel free to explore more features and capabilities of Jenkins as you continue your DevOps journey. Jenkins offers a vast ecosystem of plugins, integrations, and community support, making it a powerful tool for automating your software development processes.

Stay tuned for Day 23, where we will work on a Jenkins freestyle project for DevOps Engineers.