CKAD Application Deployment Practice Test 9 — 15 Questions

Question 1

You have a Deployment with 'replicas: 3' and the HPA is configured with 'targetCPUUtilizationPercentage: 80'. The current CPU usage is at 60% across all pods, but the HPA has scaled up to 5 replicas. What is the most likely reason?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

The CPU request in the Deployment's resource spec might be set lower than expected, causing the HPA to perceive higher utilization.. The HPA calculates CPU utilization as the average CPU usage across all pods divided by the CPU request of each pod. If the Deployment's container resource requests are set to a value that is lower than expected (e.g., 0.5 CPU instead of 1.0 CPU), then the same absolute CPU usage results in a higher utilization percentage. With 3 pods at 60% actual usage but a low CPU request, the utilization relative to the request could exceed the 80% target, triggering scale-up to 5 replicas. Therefore, option A is the most likely reason: a mismatch in the CPU request on the Deployment's resource spec causes the HPA to perceive higher utilization.

Answer

The HPA has a behavior policy that scales up aggressively

Answer

The HPA is using the 'averageUtilization' target type on a custom metric, not CPU

Answer

The HPA is reading the total CPU usage instead of average

Question 2

You are asked to implement a blue-green deployment using Kubernetes Deployments and Services. You have a blue Deployment with label 'version: blue' and a green Deployment with label 'version: green'. Both have selector 'app: myapp'. You need a Service that initially points to blue. How should you configure the Service to switch to green without downtime?

Accepted Answer

Update the Service's label selector to 'app: myapp, version: green'. Updating the Service's label selector to 'app: myapp, version: green' causes the Service to immediately route traffic to green pods without any downtime. The Service uses the selector to dynamically discover pods with matching labels, so changing the selector seamlessly shifts traffic to the green Deployment while the blue Deployment remains untouched.

Answer

Change the blue Deployment's pod label to 'version: green' and delete green Deployment

Answer

Delete the Service and recreate it with the new selector

Answer

Update the Service's cluster IP to point to green pods

Question 3

Which of the following is the correct way to scale a Deployment named 'api' to 5 replicas using kubectl?

Accepted Answer

kubectl scale deployment api --replicas=5. `kubectl scale deployment api --replicas=5` is the standard kubectl command to change the replica count of a Deployment. The `scale` subcommand directly modifies the `.spec.replicas` field in the Deployment's manifest, instructing the ReplicaSet controller to adjust the number of Pods to match the desired count.

Answer

kubectl scale deploy api 5

Answer

kubectl update deployment api --replicas=5

Answer

kubectl set replicas deployment api 5

Question 4

You have a Kustomize overlay that sets 'replicas: 5' in a patch, but the base Deployment has 'replicas: 3'. What is the final number of replicas after applying 'kubectl apply -k overlay/'?

Accepted Answer

5. In Kustomize, overlays are applied on top of the base, and patches override the base values. Since the overlay explicitly sets 'replicas: 5' via a patch, it replaces the base value of 3. The final Deployment will have 5 replicas, making D correct.

Answer

3

Answer

8

Answer

It depends on the strategy

Question 5

During a rolling update of a Deployment, you notice that new pods are failing readiness probes. The rollout is stalled. Which command would you use to abort the rollout and revert to the previous revision?

Accepted Answer

kubectl rollout undo deployment . 'kubectl rollout undo deployment ' reverts the rollout to the previous revision. Option A is correct.

Answer

kubectl rollout pause deployment <name>

Answer

kubectl rollout resume deployment <name>

Answer

kubectl delete deployment <name> --cascade=false

Question 6

You have a Deployment with the following strategy: type: Recreate. What happens when you update the pod template?

Accepted Answer

Old pods are terminated first, then new pods are created. The Recreate strategy in a Kubernetes Deployment first terminates all existing Pods before creating new ones. When the pod template is updated, the Deployment controller scales down the ReplicaSet to 0 replicas, waits for all Pods to terminate, then scales up the new ReplicaSet to the desired number of replicas. This ensures zero overlap between old and new Pods, which is useful for workloads that cannot run concurrently.

Answer

New pods are created first, then old pods are terminated

Answer

Pods are updated in-place without termination

Answer

The update is rejected because Recreate is not a valid strategy

Question 7

You run 'kubectl apply -f deployment.yaml' and later 'kubectl replace -f deployment.yaml' on the same file. What is the difference?

Accepted Answer

apply merges changes, replace replaces the entire resource. 'kubectl apply' performs a declarative three-way merge between the last-applied-configuration annotation, the live object, and the new file, so it only changes fields that differ. 'kubectl replace' performs a full replacement of the resource with the contents of the file, overwriting the entire object and failing if the resource does not exist.

Answer

apply is used for Deployments only, replace for any resource

Answer

apply requires --record flag, replace does not

Answer

apply creates, replace updates

Question 8

You have a Deployment 'web' with 'maxSurge: 25%' and 'maxUnavailable: 25%'. Current replicas is 4. You update the image. How many pods will be created at most during the rollout?

Accepted Answer

5. With maxSurge: 25% and maxUnavailable: 25%, the maximum number of pods created during a rolling update is calculated as current replicas (4) plus the surge (25% of 4 = 1), resulting in up to 5 pods at any given time. The surge allows extra pods to be created before terminating old ones, ensuring availability while limiting the total to 5.

Answer

8

Answer

4

Answer

6

Question 9

Which THREE of the following are true about using 'kubectl rollout undo'? (Select three)

Accepted Answer

It rolls back to the previous revision by default. 'kubectl rollout undo' without any flags reverts a Deployment to the previous revision (revision N-1) by default. This is the standard behavior for rollback operations in Kubernetes, where each change to a Deployment's pod template creates a new revision in the rollout history.

Answer

It pauses the current rollout

Answer

It deletes the current Deployment and recreates it from scratch

Question 10

You have a Deployment named 'web-app' with 5 replicas. You want to perform a rolling update with a maximum of 2 extra pods during the update and allow at most 1 pod to be unavailable. Which YAML snippet correctly configures the rolling update strategy?

Accepted Answer

strategy:
  type: RollingUpdate
  rollingUpdate:
    maxSurge: 2
    maxUnavailable: 1. Ly sets maxSurge to 2 and maxUnavailable to 1. maxSurge: 2 allows up to 2 extra pods above the desired 5 replicas (total 7). maxUnavailable: 1 ensures at most 1 pod is unavailable during the update, meeting the requirement of allowing at most 1 unavailable pod.

Answer

strategy:
  type: RollingUpdate
  rollingUpdate:
    maxSurge: 3
    maxUnavailable: 0

Answer

strategy:
  type: RollingUpdate
  rollingUpdate:
    maxSurge: 1
    maxUnavailable: 2

Answer

strategy:
  type: RollingUpdate
  rollingUpdate:
    maxSurge: "50%"
    maxUnavailable: "20%"

Question 11

You want to deploy an application with zero downtime by using a blue-green deployment pattern. Which Kubernetes resources are essential for implementing this strategy?

Accepted Answer

Two Deployments (blue and green) and a Service that can switch its selector. Blue-green deployments in Kubernetes require two separate Deployments (blue and green) to maintain separate environments, and a Service that can switch its selector labels to route traffic to the active deployment. Option D is correct because it describes exactly this pattern. Option A uses a single Deployment with RollingUpdate, which is a different strategy for zero downtime but not blue-green. Option B uses StatefulSet and Headless Service, which are for stateful applications and do not support blue-green switching. Option C uses a Recreate strategy, which causes downtime by terminating all pods before creating new ones, and Ingress alone cannot switch between two deployments without additional configuration.

Answer

A single Deployment with a RollingUpdate strategy

Answer

A StatefulSet and a Headless Service

Answer

A Deployment with a Recreate strategy and an Ingress

Question 12

You have deployed an application using Helm. You want to see the history of revisions for the release 'frontend' in the 'web' namespace. Which command should you use?

Accepted Answer

helm history frontend --namespace web. The command 'helm history frontend --namespace web' lists all revisions for the release 'frontend' in the 'web' namespace.

Answer

helm status frontend --namespace web

Answer

helm list frontend --namespace web

Answer

helm get manifest frontend --namespace web

Question 13

You have a Deployment that is currently paused. You want to resume the rollout and then check the status of the rollout. Which set of commands should you run?

Accepted Answer

kubectl rollout resume deployment/myapp && kubectl rollout status deployment/myapp. First, resume the rollout with 'kubectl rollout resume deployment/', then check status with 'kubectl rollout status deployment/'. Option D is correct. Option B uses 'kubectl rollout history' which shows revision history, not current status.

Answer

kubectl rollout pause deployment/myapp && kubectl rollout status deployment/myapp

Answer

kubectl rollout resume deployment/myapp && kubectl rollout history deployment/myapp

Answer

kubectl rollout undo deployment/myapp && kubectl rollout status deployment/myapp

Question 14

You need to scale a Deployment named 'api' to 10 replicas instantly. Which command should you use?

Accepted Answer

kubectl scale deployment api --replicas=10. `kubectl scale` is the dedicated imperative command to change the replica count of a Deployment instantly. It directly updates the `spec.replicas` field in the Deployment's desired state, causing the controller to immediately create or terminate Pods to match the new count.

Answer

kubectl autoscale deployment api --min=10 --max=10

Answer

kubectl patch deployment api -p '{"spec":{"replicas":10}}'

Answer

kubectl resize deployment api --replicas=10

Question 15

A HorizontalPodAutoscaler (HPA) is configured to scale a Deployment based on CPU utilization. The target CPU utilization percentage is set to 80%. The current CPU utilization is 90%. What will the HPA do?

Accepted Answer

Scale up the number of replicas. The HPA will increase the number of replicas to bring CPU utilization down towards 80%. The exact new replicas depends on the metric, but generally it scales up.

Answer

Delete the pod with the highest CPU usage

Answer

Do nothing because 90% is within acceptable range

Answer

Scale down the number of replicas