ced4568andClaude Sonnet 5
e007bcf000
Adds all 6 ROOT 02 modules (Linux system administration, storage & filesystems, the Networking Mental Model, Linux network inspection, DNS & HTTP, Linux troubleshooting) — 37 activities, each with a real lesson, demonstration/guided exercise, knowledge check, hands-on Lab, and reflection. The Networking Mental Model module (M3) gets deliberately extra depth per its "critical module" designation, with no lab by design — conceptual mastery via knowledge check and guided exercise, matching root-05-m00's own precedent. Adds 6 new hands-on Linux/networking scenarios plus 2 MCQs: linux-service-inspection (inspects the platform's own real nginx without touching it — a genuinely safe, real service-inspection target that avoids ever risking the Lab's own connectivity), linux-service-lifecycle (start/ verify/stop a fully controllable service), linux-storage-inspection, linux-network-inspection (ip/ss/getent/curl, each framed as answering one specific diagnostic question), linux-dns-http-diagnosis (a genuine DNS-resolves-but-wrong-port failure, diagnosed and fixed), and linux-troubleshooting-framework (a real missing-config-file failure, resolved via the RootNode Observe/Evidence/Hypothesis/Test/Repair/Validate/Prevent framework). All tested end-to-end via the real scenario-validation API, including negative tests confirming they fail when unsolved. Wires rootnode-linux-networking-assessment (2 required + 4 random-draw scenarios) using the existing Phase 3B assessment engine. Co-Authored-By: Claude Sonnet 5 <[email protected]>
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Guided Exercise: Narrow Down a Disk Problem on Paper
This is a paper exercise — commit to a plan before running commands in the Lab.
Your task
df -h / shows the root filesystem is 95% full. You have three suspect directories:
/var/log, /srv/cache, and /home. Write the exact sequence of du commands you'd run to
find the actual culprit, narrowing your search efficiently rather than checking everything with
maximum depth immediately.
A worked shape to check yourself against
du -sh /var/log /srv/cache /home
— one command, comparing all three top-level suspects at once. Whichever is largest, THEN
narrow further into it specifically (e.g. du -sh /srv/cache/* if that one's the culprit) rather
than deep-diving into all three from the start — this mirrors Module 1's "cheapest, fastest-
answering question first" principle.
Instructor Notes
Facilitation: Point out that running du -sh separately three times versus once with all
three paths produces the same information — the point isn't syntax, it's the "compare broadly,
then narrow" strategy.
Approximate timing: 8-10 minutes live discussion; 5 minutes self-paced.