ced4568andClaude Sonnet 5
7f6e1857c0
Upgrades six PARTIAL modules to the gold-module standard (lesson/demonstration/ knowledge-check/guided-exercise/lab(s)/reflection), preserving every existing lab activity_id and scenario_id: root-06-m03 (jobs/cronjobs/daemonsets), root-07-m04 (ingress/networkpolicy), root-07-m02 (configuration/secrets, converted in place from a bare 5-lab bank), root-09-m02 (serviceaccounts/rbac), root-09-m03 (network/supply-chain security), root-10-m03 (troubleshooting framework). root-05-m01 (20-task kubectl-fluency bank) gets a minimal bookending lesson + reflection rather than a full redesign, since each task already carries its own explanation. root-12-m01, root-capstone-m01, and root-09-m04 are promoted to READY via documented exceptions (no new activities) where adding one would misrepresent their intentional design. Wires a new rootnode-security-assessment (exam, 60min, hint_policy disabled) using the existing Phase 3B assessment engine: 3 required hands-on CORE scenarios + 4 random-draw pools covering SecurityContext, RBAC, network policy, and the 7 previously-unwired CKS MCQs. Wires the previously-unwired readiness-probe-task scenario as an OPTIONAL practice lab in root-10-m01, using the existing is_required model. Adds root-11-m01-devops-platform-thinking — an honest, lesson-only ROOT 11 orientation module naming DevOps/platform engineering practices already exercised in ROOT 05-10/12, explicit that GitOps/CI-CD/IaC/observability need lab infrastructure this platform doesn't yet provide. No fake labs. Adds infra/scripts/validate-course-content.js: cross-checks the DB against scenario/content files for duplicate ids, orphans, invalid references, cycles, sequence collisions, instructor-notes leakage, and (new) self-paced content deferring explanation to a live instructor. 0 errors against the resulting 22 courses/modules, 163 activities, 98 scenario files. No application code changed — every gap was satisfiable with existing tables (course_modules, module_activities, assessment_definitions) and the existing content-delivery pipeline. Co-Authored-By: Claude Sonnet 5 <[email protected]>
2.4 KiB
Guided Exercise: Choosing the Right Workload Primitive
Paper-and-thinking exercise before the Labs.
The scenario
Your team needs four things running in the cluster:
- A nightly database backup that must run at 2am and finish before morning.
- A log-shipping agent that must run on every node, including nodes added later.
- A one-time script to backfill a new database column, run once during this deploy.
- The main web application, always up, serving live traffic.
Your task
For each of the four, name the correct primitive (Deployment, Job, CronJob, or DaemonSet) and answer: what would go wrong if you used a Deployment for it instead?
A worked answer to check yourself against
- CronJob. A Deployment has no concept of "run on a schedule" — you'd need external tooling to trigger it repeatedly, reinventing what CronJob already does. Using a bare Job would run it once; CronJob is what recreates that Job on schedule.
- DaemonSet. A Deployment's replica count is a number, not "one per node" — nothing guarantees even coverage, and a newly added node wouldn't automatically get a copy the way a DaemonSet guarantees.
- Job. A Deployment expects its Pod to run forever; a script that's SUPPOSED to exit when done would be treated as a crash and restarted forever, which is wrong for a one-time task.
- Deployment. This is the actual always-on, N-replicas case the other three are explicitly NOT designed for.
Self-check
If you answered "Job" for #4 or "Deployment" for #1-3, revisit the lesson's decision table before the Labs — getting this choice right the first time avoids building something that technically runs but behaves wrong in a way that's easy to miss until it causes a real problem (a backup CronJob accidentally deployed as a Job that only ever runs once, for example).
Instructor Notes
Facilitation: Good as a quick individual exercise before revealing the answer — the "what would go wrong" framing forces reasoning about the CONSEQUENCE of a wrong choice, not just recall of a definition.
Approximate timing: 8-10 minutes live with discussion; 8 minutes self-paced.
Optional extension: ask what would need to be true for #1 (the nightly backup) to actually be SAFE to run as a plain Job triggered manually once, instead of a CronJob — a good check that students understand CronJob's value is specifically the SCHEDULING, not something inherent to backups.