Jenkins and DevOps Pipeline Course Notes

Introduction to Jenkins

• Jenkins is an open-source automation server.
• It aids in building, testing, and deploying software applications.
• Gwynne Faraday is the instructor.
• Jenkins is used to create a DevOps pipeline.

Understanding DevOps Pipeline

• DevOps: Combination of Development and Operations.
• DevOps Pipeline: Set of processes/tools for continuous delivery of software applications.
• Automates build, test, and deployment phases.
• Improves efficiency and reliability in software development.

Course Outline

• Building a full DevOps pipeline using:
  • Jenkins
  • Linode servers
  • GitHub
  • Docker and Docker Hub
• Project: Curriculum app in Faraday Academy GitHub organization.

Key Features of Jenkins

• Automation with Continuous Integration (CI) and Continuous Deployment (CD) pipelines.
• Watches for events in repositories and reacts (build, test, deploy).
• Provides logs of every step in the pipeline.
• Ensures consistency across testing environments.
• Large community support with numerous tutorials available.
• Plugin architecture for customization.
• Self-hosted by default.

Benefits of Using Jenkins

• Open-source and does not require payment for an enterprise plan.
• Control over configuration and deployment.
• Used by large, mid-sized, and small companies.
• Improves software delivery cycles.

Comparisons with Other CI/CD Tools

• Alternatives: Travis CI, CircleCI, GitHub Actions, GitLab CI.
• Jenkins advantages:
  • Open-source
  • Self-hosting option
  • Total control over configuration.

Potential Drawbacks of Jenkins

• Plugins: Dependency on community-supported plugins which may not be updated/documented well.
• User Interface: Considered outdated compared to modern tools.
• Documentation: Can be outdated; ensure it matches the Jenkins version used.
• Self-hosted Maintenance: Requires installation, updates, and security management.

Key Terminology

• Continuous Integration (CI): Automates integration of code changes from multiple contributors.
• Continuous Delivery (CD): Packages the app for deployment using automated tools.
• Pipeline: Defined steps that build, test, and deploy applications.
• Controller: Main instance managing Jenkins configurations and agents.
• Agents: Environments running pipeline steps.

Jenkins Architecture Overview

• App development environment on GitHub.
• Linode servers running Jenkins (controller) and Docker (deployment).
• CI/CD process initiated upon code changes.

Getting Started with Linode

• Sign up for Linode to receive a $50 credit for 60 days.
• Create servers for Jenkins and Docker.
• Access Jenkins interface via IP address.

Setting Up Jenkins

1. Access Jenkins and input initial password (fetched via SSH).
2. Install suggested plugins for easier setup.
3. Create admin user for Jenkins.

Navigating Jenkins Interface

• Top navigation and sidebar for various functionalities.
• Dashboard for job management and build history.
• Manage Jenkins for configurations and plugin management.

Installing Plugins

• Install Blue Ocean plugin for modern UI.
• Install Docker plugins for Docker integration.

Creating a Pipeline in Blue Ocean

• Connect to GitHub repository.
• Create a Jenkinsfile to define pipeline stages and steps.
• Stages include:
  • Checkout code
  • Running tests
  • Building application
  • Deploying to Docker Hub.

Environment Configuration

• Use environment variables for sensitive data (e.g., Docker credentials).
• Ensure all required software (e.g., git, node.js, npm) is installed on the server.

Conclusion

• Successfully built a DevOps pipeline using Jenkins and connected services.
• Course emphasizes hands-on experience and problem-solving.
• Additional resources and feedback encouraged through comments.

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Additional Resources: Check the ReadMe linked in the course description.