1. What is DevOps?
DevOps is a cultural and technical movement that combines software development (Dev) and IT operations (Ops). The goal is to shorten the development lifecycle and deliver high-quality software continuously. It emphasizes collaboration, automation, and monitoring throughout all stages of the software lifecycle.
2. CI/CD Pipeline Stages
- Source: Developers commit code to version control (e.g., Git).
- Build: Code is compiled, dependencies are resolved, and artifacts are created.
- Test: Automated unit, integration, and security tests validate the build.
- Release: Code is packaged and deployed to staging or production.
- Deploy: Deployed artifacts are distributed to servers or containers.
- Monitor: Metrics and logs are collected to track performance and errors.
4. Docker & Kubernetes Basics
Docker allows applications to be packaged with their dependencies into portable containers. Kubernetes orchestrates these containers across clusters of hosts, providing high availability, scaling, and deployment automation.
- Define containers using Dockerfiles
- Create multi-container applications with Docker Compose
- Use Kubernetes manifests (YAML) to define deployments, services, and ingress rules
- Apply rolling updates and self-healing mechanisms using Kubernetes
5. Rollbacks & Monitoring
- Implement health checks to detect failed deployments
- Use feature flags for controlled rollouts
- Automate rollbacks based on failed tests or degraded metrics
- Set up logging with ELK or Loki for real-time observability
- Use uptime monitoring and alerts for SLA management
