cka-sim/weak-spots-cka.md
2026-09-13 15:53:04 -06:00

14 KiB

CKA weak spots

Generated by exam from 6 attempt(s); regenerated on every end.

Domain scores (latest full exam, 2026-09-08T19:59, 14.3%)

  • ARCH 12/228 — Cluster Architecture, Installation & Configuration (25%)
  • WORK 1/151 — Workloads & Scheduling (15%)
  • NET 0/142 — Services & Networking (20%)
  • STOR 0/66 — Storage (10%)
  • TSHOOT 2/138 — Troubleshooting (30%)

Drill next (./exam drill weak)

Q03 · ARCH · Kustomize overlay (1/1 failed, last 0/5 pts, 2026-09-08T19:59)

  • ✗ overlay kustomization.yaml exists
  • ✗ resources deployed into namespace store-prod
  • ✗ store-api has 3 replicas
  • ✗ Deployment and Service carry label env=prod

Q05 · ARCH · Static pod (1/1 failed, last 0/5 pts, 2026-09-06T22:07)

  • ✗ manifest containing static-web is in /etc/kubernetes/manifests on the node
  • ✗ mirror pod static-web- is Running
  • ✗ image is nginx:1.27

Q06 · ARCH · Certificates: expiry check and user CSR (2/2 failed, last 3/6 pts, 2026-09-12T22:17)

  • ✗ CSR jane exists with signer kubernetes.io/kube-apiserver-client
  • ✗ CSR jane approved and certificate issued

Q08 · WORK · Multi-container pod with shared volume (1/1 failed, last 0/4 pts, 2026-09-08T19:59)

  • ✗ pod log-shipper Running with containers app and shipper
  • ✗ volume logs is an emptyDir mounted at /var/log in both containers
  • ✗ shipper's logs show lines written by app

Q12 · NET · NodePort Service (1/1 failed, last 0/4 pts, 2026-09-08T19:59)

  • ✗ Service shop-svc is NodePort, port 80 -> targetPort 80
  • ✗ nodePort is 30080
  • ✗ Service has endpoints

Q13 · NET · Ingress routing (1/1 failed, last 0/5 pts, 2026-09-08T19:59)

  • ✗ ingressClassName nginx and host shop.example.com
  • ✗ /api (Prefix) -> api:8080
  • ✗ / (Prefix) -> web:80

Q15 · STOR · PersistentVolume, claim and pod (1/1 failed, last 0/6 pts, 2026-09-08T19:59)

  • ✗ PV pv-data: 1Gi hostPath /mnt/data, RWO, Retain, class manual
  • ✗ PVC pvc-data Bound to pv-data
  • ✗ data-pod Running with claim mounted at /usr/share/data

Q16 · STOR · Default StorageClass and dynamic provisioning (1/1 failed, last 0/5 pts, 2026-09-08T19:59)

  • ✗ StorageClass fast-local: local-path, WaitForFirstConsumer, Delete
  • ✗ fast-local is default and standard is not
  • ✗ fast-claim picked up fast-local and is Bound
  • ✗ fast-pod Running with claim at /data

Q17 · TSHOOT · Node NotReady (3/3 failed, last 4/8 pts, 2026-09-13T01:06)

  • ✗ kubelet is active
  • ✗ kubelet is enabled (survives reboot)

Q18 · TSHOOT · Broken deployment and service (1/1 failed, last 0/7 pts, 2026-09-08T19:59)

  • ✗ all payments replicas available
  • ✗ Service payments has endpoints (selector fixed)
  • ✗ Service targetPort matches container port 80

Q19 · TSHOOT · CrashLoopBackOff diagnosis (3/3 failed, last 1/6 pts, 2026-09-13T01:06)

  • ✗ crasher.log captured and contains the DB_HOST failure
  • ✗ pod crasher Running with DB_HOST set

Q20 · TSHOOT · Control plane component failure (1/1 failed, last 0/8 pts, 2026-09-08T19:59)

  • ✗ kube-scheduler static pod manifest repaired
  • ✗ new pods get scheduled

Q25 · WORK · Taints and tolerations (1/1 failed, last 0/4 pts, 2026-09-08T19:59)

  • ✗ cka-sim-worker carries workload=batch:NoSchedule
  • ✗ deployment tolerates the taint
  • ✗ both pods Running on cka-sim-worker

Q28 · WORK · Init container prepares content (1/1 failed, last 0/4 pts, 2026-09-08T19:59)

  • ✗ pod Running, init container named setup completed
  • ✗ emptyDir 'content' shared by both containers
  • ✗ nginx serves the init-written content

Q29 · WORK · Immutable ConfigMap rotation (1/1 failed, last 1/4 pts, 2026-09-08T19:59)

  • ✗ deployment now references a different ConfigMap
  • ✗ all pods available and see mode=new

Q30 · NET · Named ports (1/1 failed, last 0/4 pts, 2026-09-08T19:59)

  • ✗ container port 80 named app-port
  • ✗ Service port 8080 -> targetPort app-port (by name)
  • ✗ readiness probe uses the named port; endpoints ready

Q33 · ARCH · Aggregated ClusterRole (1/1 failed, last 1/5 pts, 2026-09-08T19:59)

  • ✗ ops-44 has an aggregationRule with the right label
  • ✗ aggregation populated rules from the two labelled roles
  • ✗ lee can list pods and services cluster-wide

Q37 · TSHOOT · Cluster DNS is broken (3/3 failed, last 1/6 pts, 2026-09-13T01:06)

  • ✗ CoreDNS Corefile forwards to the node resolver again
  • ✗ in-cluster and external names resolve from a pod

Q38 · TSHOOT · Deployments never create pods (2/2 failed, last 0/7 pts, 2026-09-13T01:06)

  • ✗ kube-controller-manager manifest repaired and pod Running
  • ✗ a new Deployment gets a ReplicaSet and running pods

Q39 · TSHOOT · kubelet misconfiguration (2/2 failed, last 4/7 pts, 2026-09-13T01:06)

  • ✗ kubelet config points at a CA file that exists
  • ✗ kubelet active and enabled

Q40 · ARCH · kubeadm join token (1/1 failed, last 0/5 pts, 2026-09-08T19:59)

  • ✗ join.sh contains a kubeadm join with token and CA hash
  • ✗ the token in the file exists in the cluster with TTL ~2h

Q42 · NET · Egress-only NetworkPolicy (1/1 failed, last 0/4 pts, 2026-09-08T19:59)

  • ✗ applies to app=client-47, Egress only
  • ✗ DNS rule: kube-system namespace + k8s-app=kube-dns, ports 53 UDP and TCP
  • ✗ TCP 443 to 192.168.100.0/24 only

Q106 · ARCH · CRD with validation and defaults (1/1 failed, last 0/7 pts, 2026-09-10T21:07)

  • ✗ CRD exists, Namespaced, replicas has min/max and is required
  • ✗ good created with environment prod
  • ✗ replicas 0 is rejected and the message was saved
  • ✗ defaulting works: defaulted.spec.environment == dev

Q112 · NET · TLS Ingress with a generated certificate (1/1 failed, last 0/7 pts, 2026-09-10T21:07)

  • ✗ Secret portal.lab.local-tls is kubernetes.io/tls with CN portal.lab.local
  • ✗ Ingress web: class nginx, host, TLS secret, ssl-redirect annotation
  • ✗ fp.txt matches the secret's certificate fingerprint

Q115 · STOR · Bind the right local volume (1/1 failed, last 1/6 pts, 2026-09-10T21:07)

  • ✗ PVC uses a selector and is Bound to lv-nvme
  • ✗ consumer Running on the nvme node with /data mounted

Q120 · TSHOOT · Cluster facts, exactly (1/1 failed, last 0/5 pts, 2026-09-10T21:07)

  • ✗ pod-cidr and service-cidr
  • ✗ dns-ip and proxy-mode
  • ✗ cka-sim-worker3 pod CIDR

Q121 · WORK · The context's namespace (1/1 failed, last 1/6 pts, 2026-09-10T21:07)

  • ✗ Deployment ledger-14 in ac-omega (the context's namespace), 2 available, owner=ac
  • ✗ Service ledger-14 port 9000 in the same namespace
  • ✗ ns.txt has the namespace

Attempt matrix

Q Domain Title D1 E2 D3 D4 D5 D6
1 ARCH RBAC for a deployment bot 2/6 · · ✓ · ·
2 ARCH etcd snapshot · ✓ · · · ·
3 ARCH Kustomize overlay · 0/5 · · · ·
4 ARCH CustomResourceDefinition · ✓ · · · ·
5 ARCH Static pod 0/5 · · · · ·
6 ARCH Certificates: expiry check and user CSR 0/6 · · 3/6 · ·
7 WORK Rolling update & scaling · · · · · ·
8 WORK Multi-container pod with shared volume · 0/4 · · · ·
9 WORK Scheduling with node affinity and resources · · · · · ·
10 WORK ConfigMap and Secret consumption · · · · · ·
11 NET NetworkPolicy · · · · · ·
12 NET NodePort Service · 0/4 · · · ·
13 NET Ingress routing · 0/5 · · · ·
14 NET Cluster DNS · · · · · ·
15 STOR PersistentVolume, claim and pod · 0/6 · · · ·
16 STOR Default StorageClass and dynamic provisioning · 0/5 · · · ·
17 TSHOOT Node NotReady · 0/8 · · 4/8 4/8
18 TSHOOT Broken deployment and service · 0/7 · · · ·
19 TSHOOT CrashLoopBackOff diagnosis · 1/6 · · 1/6 1/6
20 TSHOOT Control plane component failure · 0/8 · · · ·
21 ARCH Helm release install and upgrade · · · ✓ · ·
22 NET Gateway API HTTPRoute · · · · · ·
23 WORK metrics-server repair and HPA · · · · · ·
24 WORK PriorityClass · · · · · ·
25 WORK Taints and tolerations · 0/4 · · · ·
26 WORK DaemonSet on every node · · · · · ·
27 WORK CronJob with a manual run · · · · · ·
28 WORK Init container prepares content · 0/4 · · · ·
29 WORK Immutable ConfigMap rotation · 1/4 · · · ·
30 NET Named ports · 0/4 · · · ·
31 WORK Parallel Job · · · · · ·
32 WORK ResourceQuota and LimitRange · · · · · ·
33 ARCH Aggregated ClusterRole · 1/5 · · · ·
34 ARCH Discover a CRD field with kubectl explain 0/4 · · ✓ · ·
35 STOR Re-bind a Released PersistentVolume · · · · · ·
36 STOR Data survives the pod · · · · · ·
37 TSHOOT Cluster DNS is broken · 1/6 · · 1/6 1/6
38 TSHOOT Deployments never create pods · · · · 0/7 0/7
39 TSHOOT kubelet misconfiguration · · · · 4/7 4/7
40 ARCH kubeadm join token · 0/5 · · · ·
41 ARCH Component versions 0/4 · · ✓ · ·
42 NET Egress-only NetworkPolicy · 0/4 · · · ·
43 NET Headless and ExternalName services · · · · · ·
101 ARCH Exact RBAC with an existing over-grant · · · · · ·
102 ARCH etcd restore · · · · · ·
103 ARCH Static pod on a relocated manifest path · · · · · ·
104 ARCH User onboarding to a working kubeconfig · · · · · ·
105 ARCH Kustomize with generators and patches · · · · · ·
106 ARCH CRD with validation and defaults · · 0/7 · · ·
107 WORK Spread, tolerate, prioritise — under a quota · · · · · ·
108 WORK Rollback to a specific revision, then pause · · · · · ·
109 WORK Native sidecar with probes and an exact report · · · · · ·
110 WORK Cluster audit to exact files · · · · · ·
111 NET Zero-trust namespace · · · · · ·
112 NET TLS Ingress with a generated certificate · · 0/7 · · ·
113 NET Gateway API canary with header match · · · · · ·
114 NET DNS down: three faults · · · · · ·
115 STOR Bind the right local volume · · 1/6 · · ·
116 STOR Migrate data between claims · · · · · ·
117 TSHOOT Worker node: three things wrong · · · · · ·
118 TSHOOT Two control-plane components down · · · · · ·
119 TSHOOT Application down for four reasons · · · · · ·
120 TSHOOT Cluster facts, exactly · · 0/5 · · ·
121 WORK The context's namespace · · 1/6 · · ·
122 ARCH Renew control-plane certificates · · · · · ·
123 TSHOOT Nothing works: kube-apiserver itself is down · · · · · ·
124 ARCH Prepare a node join without shell access to the control plane · · · · · ·
201 ARCH kubeconfig forensics · · · · · ·
202 ARCH Helm chart with CRDs, then a custom resource · · · · · ·
203 WORK Find the controller, then scale it · · · · · ·
204 WORK Which Pods get evicted first · · · · · ·
205 ARCH Kustomize: drop a ConfigMap, add an HPA, override in prod · · · · · ·
206 STOR PV, PVC and a Deployment that mounts it · · · · · ·
207 TSHOOT Resource usage scripts · · · · · ·
208 ARCH Drain a node for maintenance · · · · · ·
209 ARCH Query the API from inside a Pod · · · · · ·
210 ARCH ServiceAccount limited to two resources · · · · · ·
211 WORK DaemonSet on every node · · · · · ·
212 WORK One Pod per node, on purpose · · · · · ·
213 NET Convert an Ingress to Gateway API, then split on a header · · · · · ·
214 ARCH Certificate expiry, two ways · · · · · ·
215 NET Egress policy with paired destinations · · · · · ·
216 NET CoreDNS: back up, extend, verify · · · · · ·
217 TSHOOT Inspect a container with crictl · · · · · ·
301 ARCH etcd configuration facts · · · · · ·
302 NET Service rules on the node · · · · · ·
303 NET A second Service CIDR · · · · · ·
304 ARCH Bound tokens versus legacy tokens · · · · · ·
305 WORK Schedule without the scheduler · · · · · ·
306 STOR Grow a volume in place · · · · · ·
307 TSHOOT Node accepts nothing new · · · · · ·
308 ARCH API resource reference card · · · · · ·
309 WORK A PodDisruptionBudget that blocks maintenance · · · · · ·
310 NET Route to something outside the cluster · · · · · ·
311 ARCH Image inventory across the cluster · · · · · ·
312 WORK A Job that fails, then one that doesn't · · · · · ·
313 NET Two hosts, TLS, and a default backend · · · · · ·
314 TSHOOT A static pod that never starts · · · · · ·
315 STOR Keep the data when the claim goes · · · · · ·
316 ARCH Plan a control-plane upgrade · · · · · ·
317 TSHOOT Certificates stop being issued · · · · · ·

E = full exam, D = drill, · = not in that session, n/m = partial credit.