CKAD — Container Images & Builds

Chapter Overview

Container images are the foundation of every Kubernetes workload. The CKAD exam tests your ability to define, build, and modify container images under the Application Design and Build domain (20% of the exam).

This chapter covers everything you need — from how images work internally, to writing production-ready Dockerfiles, to managing images in a Kubernetes cluster.

What You’ll Learn

#	Topic	What’s Covered
1	Why Container Images Matter	CKAD exam relevance, image workflow, key terminology
2	How Container Images Work	Layers, naming conventions, digests, image distribution
3	Writing Dockerfiles	Instructions, COPY vs ADD, CMD vs ENTRYPOINT, K8s overrides
4	Multi-Stage Builds	Go, Node.js, Java, Python examples, size optimization
5	Building & Pushing Images	docker build, tagging, pushing, registry providers, Podman
6	Image Pull Policies	Always, IfNotPresent, Never — defaults and troubleshooting
7	Private Registry Authentication	docker-registry Secrets, imagePullSecrets, ServiceAccount
8	Modifying Container Images	kubectl set image, rolling updates, rollbacks, Pod editing
9	Security Best Practices	Minimal bases, non-root, scanning, distroless, hardening
10	Hands-On Lab & Practice	4 labs + 7 exam-style questions with answers

CKAD Exam Relevance

This chapter maps to the Application Design and Build domain:

• Define, build and modify container images
• Choose and use the right workload resource (Deployment, Job, CronJob)
• Understand multi-container Pod design patterns

Weight: ~20% of the exam score.

Prerequisites

• Basic familiarity with Docker or container concepts
• A working kubectl setup (local or cloud)
• Docker or Podman installed for running labs

Start Learning

Begin with the first topic to understand why container images are central to the CKAD exam:

Start: Why Container Images Matter →