DevOps

What is GitOps? GitOps is a modern approach to continuous deployment that uses Git as the single source of truth for declarative infrastructure and applications. Coined by Weaveworks in 2017, GitOps extends the principles of Infrastructure as Code (IaC) to the entire deployment lifecycle. Core Principles Declarative Configuration - The entire system is described declaratively Version Controlled - The desired state is stored in Git Automated Delivery - Approved changes are automatically applied Continuous Reconciliation - Agents ensure actual state matches desired state Why GitOps? Traditional deployment approaches often suffer from several challenges: ...

Introduction Troubleshooting Kubernetes can be challenging due to its distributed nature. This guide covers practical techniques I’ve used to debug production issues across dozens of clusters. The Troubleshooting Mindset When debugging Kubernetes, follow this systematic approach: Define the problem - What’s the expected vs actual behavior? Gather information - Collect logs, events, and metrics Form hypotheses - What could cause this behavior? Test hypotheses - Verify or eliminate causes Implement fix - Apply and validate the solution Essential kubectl Commands Pod Status and Events 1 2 3 4 5 6 7 8 9 10 11 # Get pod status with more details kubectl get pods -o wide # Describe pod for events and conditions kubectl describe pod <pod-name> # Get pods with specific status kubectl get pods --field-selector=status.phase=Pending # Watch pod status changes kubectl get pods -w Container Logs 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 # Get logs from a pod kubectl logs <pod-name> # Get logs from a specific container in multi-container pod kubectl logs <pod-name> -c <container-name> # Follow logs in real-time kubectl logs -f <pod-name> # Get logs from previous container instance (after restart) kubectl logs <pod-name> --previous # Get last N lines kubectl logs --tail=100 <pod-name> # Get logs with timestamps kubectl logs --timestamps <pod-name> Executing Commands in Containers 1 2 3 4 5 6 7 8 # Open a shell in a running container kubectl exec -it <pod-name> -- /bin/bash # Run a specific command kubectl exec <pod-name> -- cat /etc/config/app.yaml # Exec into a specific container kubectl exec -it <pod-name> -c <container-name> -- /bin/sh Common Issues and Solutions 1. Pod Stuck in Pending Symptoms: Pod stays in Pending state indefinitely ...

Introduction After managing Terraform codebases across multiple organizations and cloud providers, I’ve compiled these battle-tested best practices. Whether you’re starting fresh or refactoring existing infrastructure, these patterns will help you build maintainable, scalable IaC. Project Structure Standard Module Layout t ├ │ │ │ ├ │ │ │ ├ └ e ─ ─ ─ ─ r ─ ─ ─ ─ r a m ├ ├ └ e ├ ├ └ . R f o ─ ─ ─ n ─ ─ ─ t E o d ─ ─ ─ v ─ ─ ─ e A r u i r D m l n c d r d s p r M - e e o a o e t r a E p s t m t n v a o f . r w p a m / g d m o u b e i r d j r t a n n m e k e s t g - c i / e s / v t n / / e / g r / s i o n # # m m a a i i n n . . t t f f , , v t a e r r i r a a b f l o e r s m . . t t f f , v a o r u s t , p u b t a s c . k t e f n , d . v t e f r s i o n s . t f File Naming Conventions File Purpose main.tf Primary resources and module calls variables.tf Input variable declarations outputs.tf Output value declarations versions.tf Provider and Terraform version constraints locals.tf Local value definitions data.tf Data source declarations backend.tf Backend configuration Module Design Patterns 1. Single Responsibility Each module should do one thing well: ...