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>
The Q02/Q102 seeds tried to copy etcdctl out of the running etcd pod with
`kubectl exec -- cat`, which cannot work: registry.k8s.io/etcd is distroless
(no cat, no sh, no tar). The copy failed, stderr went to /dev/null and seeding
still printed a green tick, so the snapshot task had no etcdctl on the node.
Q102 was worse: it also ran `exec -- sh -c 'etcdctl ... snapshot save'` inside
that container, so its /opt/cka/backup.db was never created at all.
- etcd-tools.sh installs both binaries on the control-plane node, taking them
from the etcd image already in the node's containerd (offline, exactly the
server version), falling back to the upstream release tarball, then apt.
- setup.sh runs it at bootstrap; ensure_etcd_tools in the exam prelude installs
them through CKA_NODE_ACCESS when a task is seeded, so ssh/vagrant clusters
get them too, and both etcd setups now fail with a reason instead of hiding it.
- Q102 takes its snapshot with the node's etcdctl; Q02 no longer documents a
kubectl cp fallback that cannot work on a distroless image.
Co-authored-by: Junie <junie@jetbrains.com>