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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Guided Exercise: Predict What Survives Before You Test It
This is a paper exercise — commit to predictions before working in the Lab.
Your task
For each scenario, predict whether the data survives a docker rm -f followed by recreating a
container with the same name and image:
- Data written to
/tmp/file.txtinside a container with no volumes configured. - Data written to
/data/file.txt, where/datais mounted from a named volume. - Data written to
/data/file.txtin scenario 2, but this time you ALSO rundocker volume rm <the-volume>before recreating the container.
A worked shape to check yourself against
- Lost — no volume, so it lived only in the disposable writable layer.
- Survives — the volume itself is untouched by the container's destruction, and the new container reattaches to the same volume.
- Lost — the volume itself was explicitly deleted, not just the container. Persistence depends on the VOLUME surviving, not just avoiding container destruction.
Instructor Notes
Facilitation: Item 3 is the important trick question — students who've internalized "volumes always persist" without qualification should be corrected here: the volume itself can still be deleted deliberately.
Approximate timing: 8-10 minutes live discussion; 5 minutes self-paced.