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CNCF CKA Practice Test 18

Question 170

At Northstar finance, in an isolated training cluster during a scheduled maintenance rehearsal: The kubeadm control plane on worker-a is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. Which Kubernetes behavior best explains the required change or diagnosis?

  1. Bootstrap join tokens are sensitive credentials and a short TTL reduces the period in which a leaked token could be abused.
  2. Node labels are discoverable metadata matched by selectors; a node label alone does not create a workload restriction.
  3. A worker joins through trusted control-plane discovery and TLS bootstrap; a random API endpoint or mismatched CA hash is unsafe.
  4. Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version.

Explanation

Correct Answer

D:

Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. This explains the stated condition. The corresponding action is: Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites. The direct acceptance evidence is: Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings.

Incorrect Answers

A:

This principle describes a separate cause: Bootstrap join tokens are sensitive credentials and a short TTL reduces the period in which a leaked token could be abused. The reported condition is governed by: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. The two mechanisms should not be conflated.

B:

Node labels are discoverable metadata matched by selectors; a node label alone does not create a workload restriction. That explanation applies to a different technical failure. Here the controlling principle is: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version.

C:

The offered statement is true for this other mechanism: A worker joins through trusted control-plane discovery and TLS bootstrap; a random API endpoint or mismatched CA hash is unsafe. It does not explain the facts described here, which follow from: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version.

Question 171

At Northstar finance, in an isolated training cluster during a scheduled maintenance rehearsal: The kubeadm control plane on worker-a is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. Which observation best verifies the requested outcome rather than an unrelated state?

  1. Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings.
  2. Check the authorized join operation completes and inspect sudo kubeadm token list for expected expiry.
  3. Run kubectl describe node worker-a and inspect the Taints field for the intended key, value and effect.
  4. Run kubectl get node worker-a --show-labels and inspect workloads' node selectors.

Explanation

Correct Answer

A:

Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings. This validates the affected object or control path, rather than only showing a command completed. The underlying reason is: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. The intended action is: Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites.

Incorrect Answers

B:

That test belongs to another control with this basis: Bootstrap join tokens are sensitive credentials and a short TTL reduces the period in which a leaked token could be abused. In the current case, the governing reason is: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. The direct verification is “Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings”.

C:

This observation would test a different technical dependency: A NoSchedule taint repels Pods without a matching toleration but does not automatically evict already running Pods. The current issue is governed by: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. Its decisive check is “Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings”.

D:

The alternative verifies a different condition: Node labels are discoverable metadata matched by selectors; a node label alone does not create a workload restriction. The current case instead depends on: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. Confirm that “Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings”.

Question 172

At Northstar finance, in an isolated training cluster during a scheduled maintenance rehearsal: The kubeadm control plane on worker-a is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. Which operational control most directly prevents this failure or configuration drift?

  1. Store join credentials only in approved short-lived channels and verify the new node is assigned to the intended cluster.
  2. Require a validated backup and version-skew plan before applying kubeadm upgrades.
  3. Test restoration in an isolated environment and protect snapshot files as sensitive cluster state.
  4. Gate control-plane upgrades on tested backup, maintenance sequencing and rollback procedures.

Explanation

Correct Answer

B:

Require a validated backup and version-skew plan before applying kubeadm upgrades. This reduces recurrence of the specific operational failure. It reinforces the action: Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites. The relevant mechanism is: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version.

Incorrect Answers

A:

That safeguard is relevant to: A worker joins through trusted control-plane discovery and TLS bootstrap; a random API endpoint or mismatched CA hash is unsafe. The current failure instead follows from: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. Its prevention measure is “Require a validated backup and version-skew plan before applying kubeadm upgrades”.

C:

The suggested review tracks a different technical risk: A consistent etcd snapshot preserves control-plane state; an unauthenticated network copy is not a substitute. Here the sustained control must address: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. Choose “Require a validated backup and version-skew plan before applying kubeadm upgrades”.

D:

That safeguard is relevant to: Kubeadm upgrade apply updates the managed control-plane configuration; kubelet packages and other nodes require separate coordinated work. The current failure instead follows from: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. Its prevention measure is “Require a validated backup and version-skew plan before applying kubeadm upgrades”.

Question 173

At Horizon observability, in a disposable simulated environment during a monitored release window: The kubeadm control plane on worker-b is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. Which command or initial safe diagnostic step best addresses the stated lab task?

  1. On the control-plane host with the matching kubeadm package, run sudo kubeadm upgrade apply v1.35.3 after backups and component compatibility checks.
  2. On the control-plane host with the matching kubeadm package, run sudo kubeadm upgrade apply v1.35.2 after backups and component compatibility checks.
  3. Execute the verified kubeadm join command generated on the control plane with the token and CA certificate hash; do not invent these values.
  4. Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites.

Explanation

Correct Answer

D:

Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites. This is the appropriate command-line action or first safe diagnostic. The technical reason is: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. Validate the result with: Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings. Execute changes only in an authorized disposable lab or after normal production change controls. Applied here, the relevant facts are: on worker-b is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. The question asks which command or initial safe diagnostic step best addresses the stated lab task.

Incorrect Answers

A:

This alternative is a response to another technical cause: Kubeadm upgrade apply updates the managed control-plane configuration; kubelet packages and other nodes require separate coordinated work. The reported case instead depends on: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. The action that directly addresses it is “Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites”.

B:

The proposed action belongs to the mechanism: Kubeadm upgrade apply updates the managed control-plane configuration; kubelet packages and other nodes require separate coordinated work. Here the stated fault follows a different mechanism: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. The corrective choice is “Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites”.

C:

The offered action targets: A worker joins through trusted control-plane discovery and TLS bootstrap; a random API endpoint or mismatched CA hash is unsafe. The case facts point instead to: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. Implement “Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites” to address that specific condition.

Question 174

At Horizon observability, in a disposable simulated environment during a monitored release window: The kubeadm control plane on worker-b is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. Which Kubernetes behavior best explains the required change or diagnosis?

  1. Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version.
  2. A NoSchedule taint repels Pods without a matching toleration but does not automatically evict already running Pods.
  3. Bootstrap join tokens are sensitive credentials and a short TTL reduces the period in which a leaked token could be abused.
  4. A consistent etcd snapshot preserves control-plane state; an unauthenticated network copy is not a substitute.

Explanation

Correct Answer

A:

Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. This explains the stated condition. The corresponding action is: Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites. The direct acceptance evidence is: Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings. Applied here, the relevant facts are: on worker-b is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. The question asks which Kubernetes behavior best explains the required change or diagnosis.

Incorrect Answers

B:

The offered statement is true for this other mechanism: A NoSchedule taint repels Pods without a matching toleration but does not automatically evict already running Pods. It does not explain the facts described here, which follow from: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version.

C:

This principle describes a separate cause: Bootstrap join tokens are sensitive credentials and a short TTL reduces the period in which a leaked token could be abused. The reported condition is governed by: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. The two mechanisms should not be conflated.

D:

A consistent etcd snapshot preserves control-plane state; an unauthenticated network copy is not a substitute. That explanation applies to a different technical failure. Here the controlling principle is: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version.

Question 175

At Horizon observability, in a disposable simulated environment during a monitored release window: The kubeadm control plane on worker-b is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. Which observation best verifies the requested outcome rather than an unrelated state?

  1. Run kubectl get node worker-b and verify that SchedulingDisabled is absent.
  2. Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings.
  3. Run sudo etcdutl snapshot status /var/backups/metrics-api.db -w table and confirm a readable snapshot.
  4. Run kubectl describe node worker-b and inspect the Taints field for the intended key, value and effect.

Explanation

Correct Answer

B:

Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings. This validates the affected object or control path, rather than only showing a command completed. The underlying reason is: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. The intended action is: Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites. Applied here, the relevant facts are: on worker-b is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. The question asks which observation best verifies the requested outcome rather than an unrelated state.

Incorrect Answers

A:

That test belongs to another control with this basis: Uncordon clears the Node's unschedulable status; it does not guarantee any particular Pod will be placed there. In the current case, the governing reason is: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. The direct verification is “Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings”.

C:

The alternative verifies a different condition: A consistent etcd snapshot preserves control-plane state; an unauthenticated network copy is not a substitute. The current case instead depends on: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. Confirm that “Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings”.

D:

That test belongs to another control with this basis: A NoSchedule taint repels Pods without a matching toleration but does not automatically evict already running Pods. In the current case, the governing reason is: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. The direct verification is “Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings”.

Question 176

At Horizon observability, in a disposable simulated environment during a monitored release window: The kubeadm control plane on worker-b is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. Which operational control most directly prevents this failure or configuration drift?

  1. Avoid logging join tokens and rotate or expire temporary bootstrap credentials promptly.
  2. Reserve and govern security-sensitive scheduling labels through controlled change procedures.
  3. Require a validated backup and version-skew plan before applying kubeadm upgrades.
  4. Record node maintenance ownership and uncordon obligations before opening a window.

Explanation

Correct Answer

C:

Require a validated backup and version-skew plan before applying kubeadm upgrades. This reduces recurrence of the specific operational failure. It reinforces the action: Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites. The relevant mechanism is: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. Applied here, the relevant facts are: on worker-b is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. The question asks which operational control most directly prevents this failure or configuration drift.

Incorrect Answers

A:

This routine guards against another mechanism: Bootstrap join tokens are sensitive credentials and a short TTL reduces the period in which a leaked token could be abused. The recurring exposure in the current case is: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. The matching preventive check is “Require a validated backup and version-skew plan before applying kubeadm upgrades”.

B:

The suggested review tracks a different technical risk: Node labels are discoverable metadata matched by selectors; a node label alone does not create a workload restriction. Here the sustained control must address: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. Choose “Require a validated backup and version-skew plan before applying kubeadm upgrades”.

D:

This routine guards against another mechanism: Cordon marks a Node unschedulable to new Pods but does not drain running workloads. The recurring exposure in the current case is: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. The matching preventive check is “Require a validated backup and version-skew plan before applying kubeadm upgrades”.

Question 177

At Pinecrest logistics, in a sandbox Kubernetes cluster during a recovery tabletop exercise: The kubeadm control plane on worker-c is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. Which command or initial safe diagnostic step best addresses the stated lab task?

  1. Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites.
  2. Run helm upgrade --install dispatch-api ./charts/dispatch-api --namespace fulfillment --create-namespace --set replicaCount=5 after inspecting values.
  3. On the control-plane host with the matching kubeadm package, run sudo kubeadm upgrade apply v1.35.1 after backups and component compatibility checks.
  4. On the control-plane host with the matching kubeadm package, run sudo kubeadm upgrade apply v1.35.2 after backups and component compatibility checks.

Explanation

Correct Answer

A:

Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites. This is the appropriate command-line action or first safe diagnostic. The technical reason is: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. Validate the result with: Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings. Execute changes only in an authorized disposable lab or after normal production change controls. Applied here, the relevant facts are: on worker-c is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. The question asks which command or initial safe diagnostic step best addresses the stated lab task.

Incorrect Answers

B:

The offered action targets: Helm maintains release revisions and renders templates; an install-or-upgrade path avoids treating an existing release as a new deployment. The case facts point instead to: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. Implement “Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites” to address that specific condition.

C:

This alternative is a response to another technical cause: Kubeadm upgrade apply updates the managed control-plane configuration; kubelet packages and other nodes require separate coordinated work. The reported case instead depends on: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. The action that directly addresses it is “Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites”.

D:

The proposed action belongs to the mechanism: Kubeadm upgrade apply updates the managed control-plane configuration; kubelet packages and other nodes require separate coordinated work. Here the stated fault follows a different mechanism: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. The corrective choice is “Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites”.

Question 178

At Pinecrest logistics, in a sandbox Kubernetes cluster during a recovery tabletop exercise: The kubeadm control plane on worker-c is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. Which Kubernetes behavior best explains the required change or diagnosis?

  1. A consistent etcd snapshot preserves control-plane state; an unauthenticated network copy is not a substitute.
  2. Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version.
  3. Bootstrap join tokens are sensitive credentials and a short TTL reduces the period in which a leaked token could be abused.
  4. Cordon marks a Node unschedulable to new Pods but does not drain running workloads.

Explanation

Correct Answer

B:

Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. This explains the stated condition. The corresponding action is: Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites. The direct acceptance evidence is: Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings. Applied here, the relevant facts are: on worker-c is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. The question asks which Kubernetes behavior best explains the required change or diagnosis.

Incorrect Answers

A:

The offered statement is true for this other mechanism: A consistent etcd snapshot preserves control-plane state; an unauthenticated network copy is not a substitute. It does not explain the facts described here, which follow from: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version.

C:

Bootstrap join tokens are sensitive credentials and a short TTL reduces the period in which a leaked token could be abused. That explanation applies to a different technical failure. Here the controlling principle is: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version.

D:

The offered statement is true for this other mechanism: Cordon marks a Node unschedulable to new Pods but does not drain running workloads. It does not explain the facts described here, which follow from: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version.

Question 179

At Pinecrest logistics, in a sandbox Kubernetes cluster during a recovery tabletop exercise: The kubeadm control plane on worker-c is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. Which observation best verifies the requested outcome rather than an unrelated state?

  1. Run kubectl get pods -A -o wide --field-selector spec.nodeName=worker-c and review remaining DaemonSets.
  2. Run kubectl get nodes from the control plane and confirm worker-a becomes Ready after CNI initialization.
  3. Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings.
  4. Check the authorized join operation completes and inspect sudo kubeadm token list for expected expiry.

Explanation

Correct Answer

C:

Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings. This validates the affected object or control path, rather than only showing a command completed. The underlying reason is: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. The intended action is: Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites. Applied here, the relevant facts are: on worker-c is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. The question asks which observation best verifies the requested outcome rather than an unrelated state.

Incorrect Answers

A:

This observation would test a different technical dependency: Drain cordons the node and requests evictions for eligible Pods; the ignore-daemonsets flag is needed because DaemonSet Pods are not deleted by drain. The current issue is governed by: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. Its decisive check is “Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings”.

B:

The alternative verifies a different condition: A worker joins through trusted control-plane discovery and TLS bootstrap; a random API endpoint or mismatched CA hash is unsafe. The current case instead depends on: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. Confirm that “Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings”.

D:

This observation would test a different technical dependency: Bootstrap join tokens are sensitive credentials and a short TTL reduces the period in which a leaked token could be abused. The current issue is governed by: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. Its decisive check is “Inspect the reported current and candidate versions, component compatibility and upgrade preflight warnings”.

Question 180

At Pinecrest logistics, in a sandbox Kubernetes cluster during a recovery tabletop exercise: The kubeadm control plane on worker-c is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. Which operational control most directly prevents this failure or configuration drift?

  1. Gate control-plane upgrades on tested backup, maintenance sequencing and rollback procedures.
  2. Include schedulability restoration in maintenance completion checklists.
  3. Avoid logging join tokens and rotate or expire temporary bootstrap credentials promptly.
  4. Require a validated backup and version-skew plan before applying kubeadm upgrades.

Explanation

Correct Answer

D:

Require a validated backup and version-skew plan before applying kubeadm upgrades. This reduces recurrence of the specific operational failure. It reinforces the action: Run sudo kubeadm upgrade plan on the eligible control-plane host after checking package and version prerequisites. The relevant mechanism is: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. Applied here, the relevant facts are: on worker-c is due for a supported Kubernetes version review before a maintenance upgrade. Work only within the stated target and verify before declaring success. The question asks which operational control most directly prevents this failure or configuration drift.

Incorrect Answers

A:

The suggested review tracks a different technical risk: Kubeadm upgrade apply updates the managed control-plane configuration; kubelet packages and other nodes require separate coordinated work. Here the sustained control must address: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. Choose “Require a validated backup and version-skew plan before applying kubeadm upgrades”.

B:

That safeguard is relevant to: Uncordon clears the Node's unschedulable status; it does not guarantee any particular Pod will be placed there. The current failure instead follows from: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. Its prevention measure is “Require a validated backup and version-skew plan before applying kubeadm upgrades”.

C:

This routine guards against another mechanism: Bootstrap join tokens are sensitive credentials and a short TTL reduces the period in which a leaked token could be abused. The recurring exposure in the current case is: Upgrade plan reports reachable upgrade targets and version skew considerations without applying a new control-plane version. The matching preventive check is “Require a validated backup and version-skew plan before applying kubeadm upgrades”.