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]>
1.4 KiB
Demonstration: Answering the Five Questions For Real
OBSERVE
This Lab's own terminal is served by a real running service: nginx.
$ pgrep -x nginx
906
Something with PID 906 is running.
HYPOTHESIS
Predict: where would nginx's configuration file be, and where would its logs be?
INSPECT
$ cat /etc/nginx/nginx.conf | head -5
worker_processes 1;
error_log /var/log/nginx/error.log warn;
pid /run/nginx.pid;
...
$ ls /var/log/nginx/
access.log error.log
CHANGE
Confirm it's actually listening on the port you'd expect:
$ ss -lnt | grep :80
LISTEN 0 511 0.0.0.0:80 0.0.0.0:*
VERIFY
All five questions answered with real evidence, not assumptions: it's running (PID 906),
listening on port 80, configured at /etc/nginx/nginx.conf, logging to /var/log/nginx/. This
exact sequence — process, port, config, logs — is what you'll repeat for almost any unfamiliar
service on any real system.
Instructor Notes
Demo goal: Show the five-question checklist answered end-to-end against a real, already- running service the students are themselves using right now — more convincing than an abstract example.
Approximate timing: 8 minutes live.
Common mistake to watch for: stopping here at "PID exists" without also confirming it's actually listening on the expected port — a process existing and a service actually being reachable are two different facts, both worth checking.