55ab18f814
2 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
| 55ab18f814 |
fix: repair the CKA bank and harness after a live audit; add Simulator Set D
Every changed task was seeded, graded untouched, solved and re-graded on a separate kind cluster. The four sim sets were rehearsed as full sittings (real baseline, seed everything, solve in order, grade at the end): A 150/150, B 176/176, C 163/163, D 122/122. Every random-pool task was either passed in a real session or cycled the same way. Graders that could never pass, or passed for free: Q306 (local-path cannot resize; now graded as an in-place resize), Q314 (GNU grep prefixed file names), Q305 (plain `get events` has no SOURCE column and events expire; now managedFields), Q410 (kindnet DOES enforce NetworkPolicy; the expected answer is now derived from the CNI), Q35, Q212 (missing `]`), Q101 (`can-i create pods/exec` asks about a pod NAMED exec; multi-type get), Q109 (an emptyDir over nginx's /var/log crash-loops it), Q40 (TTL was measured at grading time), Q121, Q106, Q104, Q41, Q26, Q403, Q409, Q417, Q113, Q22, Q24/Q108 (flaky right after a rollout), and free points on untouched Q24/Q102/Q108/Q119/Q122. Reference solutions: S[43], S[107], S[121], S[106] rewritten; S[116] (a Completed Job pod still pins its PVC), S[119] (a pods quota equal to replicas deadlocks the rollout); DNS checks use FQDNs; the explainer and exam guide are corrected (etcd restore is etcdutl's job on 3.6+). Cross-session leaks: the pre-session baseline now also repairs Q114 (the kube-system NetworkPolicy and CoreDNS replicas), Q117/Q39 kubelet CA paths, Q317, kubelet drop-in binary paths, a moved scheduler manifest, leftover static pods and the default StorageClass. Q115 releases its fixed PVs from claims left by earlier sessions. Conflicts: `breaks` may be a list and `solo` keeps Q102's etcd restore out of mixed sessions. Q118, Q5/Q103, Q26 vs the W1 taints, set A 203/204/208/212 and set B 305/309 no longer sabotage each other. Q317 now disables only CSR signing (the old break killed the whole controller-manager). Q110/Q311 no longer compare against the whole cluster at submit time. Two delete/recreate races in setups are fixed. Harness: the weak list clears after two clean passes in a row, weak entries show the latest attempt's failures, domain scores use the exam's own tasks, history entries can be marked synthetic (entry 11 is), the web UI lists every sim set, `./exam grade` refuses mid-exam (--force), preflight checks W1. Set D (`./exam sim d`): 17 original killer.sh-style tasks, ids 501-517, 122 points - control-plane inventory, event forensics with crictl, a broken kubelet unit, kubelet certificates, manual scheduling with the scheduler stopped, Helm housekeeping with a stuck release, an enforced AND-vs-OR NetworkPolicy, dnsPolicy and access-mode troubleshooting, and more. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> |
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| 65c2fbfd43 |
feat: Simulator Set C - 18-task mock modelled on a commercial CKA sitting
`./exam sim c` - 18 tasks, 163 points, 120 minutes, exam rules. Built after a
23% result on a paid mock, so reruns cost nothing and the weak topics can be
drilled as often as needed.
Original scenarios, not copies, exercising the same techniques as an 18-question
sitting: hostPath PV/PVC bound by volumeName, data migration between claims onto
a Retain volume, Helm render-then-install, Gateway API header canary, RBAC with
the answer written to a file, probe/selector/targetPort repair, HPA v2 behavior
blocks, and three "write the output to an exact path" data-extraction tasks.
Ids 401-418, set="c", difficulty="hard". cmd_sim is already generic over SETS so
no harness change was needed; set-tagged tasks stay out of POOL and cannot leak
into `./exam start` or drills. CKA bank goes 101 -> 119 tasks.
Two scenarios are deliberately adapted, because the originals would destroy the
practice cluster:
- 410 audits the installed CNI and applies a default-deny, rather than
installing Calico over the running kindnet. The Flannel-vs-Calico
"does this CNI actually enforce NetworkPolicy" judgement is kept as a
written answer.
- 413 plans a control-plane upgrade - versions, ordered command sequence,
`kubeadm upgrade node` for workers - and never runs `kubeadm upgrade apply`.
The grader checks the ordering, modelled on Q316.
Verified end to end: every task seeded, solved with its own reference solution
and graded, 163/163 across all 18, in four batches. Checks were also confirmed
to fail cleanly against an unsolved cluster rather than erroring.
Three environment facts cost a round of debugging and are now encoded in the
tasks and their solutions:
- The StorageClass on this kind cluster is named `standard`, not `local-path`,
and is WaitForFirstConsumer - a PVC stays Pending until its pod can be
scheduled, which is what interlocks the two faults in 414.
- Under rootless podman the host cannot route to node IPs, so a host-side
openssl against a NodePort just hangs (rc=124). 417 probes TLS from inside a
node via nx against 127.0.0.1:<nodePort>. Nodes have openssl and curl but
not nc or wget.
- hostPath PV data must be seeded on every node (401, 405), since nothing
pins the pod to the node holding the directory.
Seeding all 18 creates ~24 pods, which on this host needs
kernel.keys.maxkeys raised above the 200 default or container starts fail with
"unable to join session keyring: disk quota exceeded".
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NziZdvBvy7CpEAAbZNgp8i
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