ced4568andClaude Sonnet 5
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Adds all 8 ROOT 04 modules (why containers exist, images & containers, Docker CLI, container networking, container storage, Dockerfile & image build, Docker Compose, containers → Kubernetes) — 43 activities, using the nested Docker Engine Phase 6D built and tested. Modules 1, 2, and 8 are conceptual (no lab by design) — the honest bridge module (M8) explicitly names what Kubernetes adds beyond what this course already taught, without re-teaching Kubernetes itself. Adds 5 new hands-on Docker scenarios plus 2 MCQs, all against the real nested Docker Engine: docker-cli-basics (run/exec/inspect a real container), docker-container-networking (a genuine "works internally, unreachable from host" port-publishing failure, diagnosed and fixed by recreating the container with the correct `-p` flag), docker-container-storage (a real destroy/recreate cycle proving named-volume persistence, not just described), docker-build-image (a real Dockerfile, a real build, a real custom image run), and docker-compose-multiservice (a real two-service Compose application with a real published port). All tested end-to-end via the real scenario-validation API, including negative tests. Wires rootnode-containers-assessment (2 required + 4 random-draw scenarios) using the existing Phase 3B assessment engine. This completes the entire ROOT_ Foundations sequence (ROOT 01-04) — see docs/PHASE6E_ROOT_FOUNDATIONS_COMPLETION.md. Co-Authored-By: Claude Sonnet 5 <[email protected]>
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Knowledge Check: Docker Compose
1. What does depends_on actually guarantee — and NOT guarantee?
Answer: It guarantees START order (the dependency's container is started before the dependent service's). It does NOT guarantee the dependency is actually READY/healthy yet — a real, common source of race conditions in production Compose files.
2. Do you need to manually run docker network create for services in the same Compose file
to reach each other by name?
Answer: No — Compose automatically creates a shared network for all services defined in the file, and they can reach each other by service name immediately.
3. What does docker compose down clean up, that plain docker compose stop would not?
Answer: down removes the containers AND the network Compose created; stop only stops the
containers, leaving them (and the network) in place to be restarted later.
4. Does Compose introduce any concept that isn't already just automating docker run/
docker network commands you already know?
Answer: No — every Compose service maps directly onto concepts already covered (image, ports, networking); Compose automates and declaratively describes them, it doesn't add new underlying mechanisms.
Instructor Notes
Facilitation: Question 1 is worth real emphasis — it's a genuine, common production mistake worth preventing early.
Approximate timing: 5 minutes.