Docker Kubernetes Study Notes

Blue-Green and Canary Deployments

How to safely release new application versions to production using zero-downtime blue-green switches and gradual canary rollouts.

CI/CD Pipelines for Containers

How to design continuous integration and delivery pipelines that build, test, scan, and deploy containerized applications to Kubernetes.

Common Docker & Kubernetes Pitfalls

The recurring mistakes engineers make with Docker and Kubernetes in production, why they happen, and how to avoid or fix each one.

ConfigMaps and Secrets

Learn how to externalize configuration and sensitive data from container images using ConfigMaps and Secrets in Kubernetes.

Container Networking Basics

Understand Docker's default bridge network, port publishing, and how containers discover and communicate with each other on user-defined networks.

Container Orchestration Strategies

A comparison of orchestration platforms and hosting models for running containers reliably at scale in production.

Container Registries

How container registries store, version, and distribute Docker images, covering tagging conventions, authentication, and push/pull workflows.

Containers vs Virtual Machines

A technical comparison of containers and virtual machines covering architecture, resource usage, startup time, isolation strength, and typical use cases.

Deployments and ReplicaSets

Learn how Deployments manage ReplicaSets to declaratively run, scale, and update stateless Pod replicas in Kubernetes.

Docker Architecture Overview

An overview of Docker's client-server architecture, including the Docker daemon, CLI client, images, containers, and registries.

Docker Compose Basics

Learn how Docker Compose defines and runs multi-container applications from a single YAML file, replacing long manual docker run commands.

Docker Images Explained

An introduction to what Docker images are, how they differ from containers, and how their layered, read-only filesystem structure works.

Docker & Kubernetes Interview Questions

A curated set of frequently asked Docker and Kubernetes interview questions with thorough answers spanning images, networking, pods, and scaling.

Docker & Kubernetes Quick Reference

A cheat-sheet of essential Docker CLI commands, kubectl commands, Dockerfile instructions, and kubectl resource shortnames for fast lookup.

Docker Security Basics

Defensive practices for hardening container images and runtime, including non-root users, minimal base images, vulnerability scanning, and dropped capabilities.

Environment Variables and Configuration

Learn how to configure containerized applications using environment variables, .env files, and Dockerfile defaults without rebuilding images.

Health Checks and Restart Policies

How Docker uses HEALTHCHECK instructions and restart policies to detect unhealthy containers and automatically recover from failures.

Helm Package Manager

Understand how Helm charts template and version Kubernetes manifests, and how to install, upgrade, and roll back releases.

Horizontal Pod Autoscaling

Learn how the HorizontalPodAutoscaler automatically adjusts replica counts based on CPU, memory, or custom metrics to match workload demand.

Image Layers and Build Caching

How Docker's layered filesystem and build cache work, and how to order Dockerfile instructions to maximize cache hits and minimize image size.

Image Size Optimization

Techniques for shrinking Docker images through multi-stage builds, minimal base images, and layer-aware Dockerfile authoring to speed up builds and deployments.

Ingress Controllers

Learn how Ingress resources and Ingress controllers expose HTTP/HTTPS routing, host- and path-based rules, and TLS termination for cluster Services.

Installing and Using the Docker CLI

A practical guide to installing Docker and using its core CLI commands for pulling images, running containers, and inspecting Docker's state.

Jobs and CronJobs

Learn how Kubernetes Jobs run Pods to completion for batch work, and how CronJobs schedule Jobs on a recurring, cron-style schedule.