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>
Two things in one regeneration of the data files:
- Stripped "pauses" and "paused_seconds" from all 10 existing entries, so the
data matches the code change in 01877f0 rather than leaving historical
telemetry behind. Nothing else in those entries was touched.
- Attempt #11: Simulator Set C, 163/163. Recorded for completeness, but it is
not a measure of skill - the tasks were completed programmatically to verify
the new bank end to end on a freshly seeded cluster, not solved by hand.
Set C tasks carry set="c" and are excluded from POOL, so this does not
affect `./exam drill weak` or `./exam drill all` selection; `./exam sim c`
re-runs the full set regardless of history.
The genuine result from this week is attempt #10: an 18-task drill at 39.7%,
8 of 11 attempted tasks at full credit, 7 never opened.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NziZdvBvy7CpEAAbZNgp8i
Close two of the four CKA-relevant gaps identified against Killercoda's
scenario catalog:
- Q123 (TSHOOT, hard): kube-apiserver itself crash-loops on a static-pod
manifest typo, same pattern as the existing scheduler/controller-manager
failures (Q20/Q118) but with the added twist that kubectl is completely
unusable until it's fixed, forcing node-level diagnosis (crictl,
journalctl).
- Q124 (ARCH, hard): produce a real node-join handoff file by
independently computing the CA discovery hash kubeadm join verifies
against, and finding the API server's actual in-cluster address rather
than the local kubeconfig's port-forwarded one.
Cluster-upgrade and operator-authoring remain unimplemented and are
documented as genuine infrastructure gaps in CKA_SOLUTIONS_EXPLAINED.md
(kind's node images have no apt-installable multi-version kubelet/kubeadm,
and operator authoring needs a real built/pushed image) rather than faked.
Also updates the Killercoda cross-reference table with the gaps closed,
and logs an ended drill session to history-cka.jsonl/weak-spots-cka.md.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
