Complete DevOps and SDLC Tutorial for Beginners | What is DEVOPS | What is SDLC

 

✅ Complete DevOps and SDLC Tutorial for Beginners

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1. What is DevOps?

• Definition:
  DevOps stands for Development and Operations.
  It is a culture and practice that combines software development (Dev) and IT operations (Ops) to shorten the development lifecycle and deliver high-quality software continuously.

• Purpose:
  DevOps automates the software deployment process using CI/CD pipelines, eliminating manual deployment steps.

• Key Benefits:

  • Faster software delivery.

  • Improved collaboration between teams.

  • Reduced risk of deployment failures.

  • Continuous improvement and feedback loop.

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CI/CD in DevOps

• CI (Continuous Integration):

  • Developers integrate code frequently into a shared repository (e.g., GitHub).

  • Automated build and test process after every integration.

• CD (Continuous Deployment/Delivery):

  • Continuous Delivery: Automatically deploys code to a staging environment after passing tests.

  • Continuous Deployment: Deploys code directly to production without manual intervention.

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Role of a DevOps Engineer

• Acts as a bridge between:

  • Developers → who write the code.

  • QA → who test the code.

  • Networking & Server Admin → who manage infrastructure.

  • Support Team → who ensure system stability.

• Main responsibility: Automate processes, create CI/CD pipelines, and manage cloud/infrastructure.

2 DevOps Lifecycle

The DevOps process includes:

1. Plan: Requirement analysis & sprint planning.

2. Code: Develop software using Git, IDEs.

3. Build: Compile and package code (e.g., Maven, Gradle).

4. Test: Automated testing using tools like Selenium.

5. Release: Deploy to production environment.

6. Deploy: Continuous Deployment with Jenkins, Docker.

7. Operate: Application runs on servers/cloud.

8. Monitor: Monitor performance using Prometheus, Grafana.

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3. What is SDLC?

• Definition:
  SDLC stands for Software Development Life Cycle.
  It is a step-by-step process to develop software in a structured way.

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Phases of SDLC

1. Requirement Gathering

2. Design

3. Development

4. Testing

5. Deployment

6. Maintenance

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Popular Models of SDLC

• Waterfall Model

• V-Model

• Spiral Model

• Agile Model (Most Preferred Today)

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Agile Model

• Works on small planning using Sprints (short development cycles).

• Scrum Team:

  • Scrum Master → Facilitates the team.

  • Developers, QA, DevOps → Implement and test features.

  • End User/Product Owner → Provides feedback.

• Stand-up Meetings: Daily 15-minute meetings to discuss progress, blockers, and plans.

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4. Tools Used in DevOps

a) Code Management

• Git: Distributed version control system.

• GitHub: Remote repository for storing code and collaborating.

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b) Build Automation

• Maven, Gradle, or Ant.

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c) CI/CD Tools

• Jenkins, GitLab CI, Azure DevOps, CircleCI.

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d) Configuration Management

• Ansible, Chef, Puppet.

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e) Containerization

• Docker, Kubernetes.

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f) Monitoring

• Prometheus, Grafana, Nagios.

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5. Simple DevOps Workflow

1. Developer writes code → pushes to GitHub.

2. CI Tool (Jenkins) detects changes → runs build → tests code.

3. Code deployed automatically to Staging Server.

4. After approval → deployed to Production Server.

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6. Quick Hands-On (Beginner Exercise)

✅ Install Git
✅ Create GitHub Repository
✅ Push Code from Local to GitHub
✅ Install Jenkins (on local or cloud)
✅ Create a simple CI/CD pipeline using Jenkins