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ced4568andClaude Sonnet 5 682ef2de47 feat(root04): author Containers & Docker
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]>
2026-08-26 17:08:14 -05:00

1.3 KiB

Reflection: A Real Multi-Service Application, Described and Running

Reflection questions

  1. Before this module, how would you have run two related containers and connected them manually? How does that compare to this module's Lab?
  2. What does a Compose file's services: block remind you of, from ROOT_'s later Kubernetes content — even without knowing Kubernetes syntax yet?

Real Ops takeaway

You just described and ran a real multi-container application declaratively — the exact same "describe what you want, let the tool make it real" pattern behind every later Kubernetes manifest in this program. This isn't a coincidence: Compose and Kubernetes both solve "orchestrate multiple containers as one application," at different scales. The habit of thinking in terms of declared services rather than manual step-by-step commands is what ROOT 05 builds on directly.

This module is complete. Continue to the final module of this course.

Instructor Notes

Discussion questions for a live classroom: question 2 previews Kubernetes manifests directly — a good moment to name "declarative description of desired state" as a term students will hear constantly starting in ROOT 05.

Approximate timing: 5-8 minutes live discussion; 5 minutes self-paced writing.