CKAD Practice Test 10 — 10 Questions

Question 1

You want to perform a blue-green deployment using Deployments and Services. You have two Deployments: 'app-blue' (current) and 'app-green' (new). The Service 'app-service' currently selects pods with label 'version: blue'. What kubectl command should you run to switch traffic to the green deployment?

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

Accepted Answer

kubectl patch service app-service -p '{"spec":{"selector":{"version":"green"}}}'. A Kubernetes Service routes traffic based on its label selector, so blue-green switching is achieved by changing the Service's selector to point at the new pods. The kubectl patch command with a strategic merge patch on spec.selector updates the selector in place, instantly redirecting traffic to pods labeled version: green without recreating the Service or changing its ClusterIP. This is the canonical, non-disruptive way to flip traffic between blue and green Deployments.

Answer

kubectl delete service app-service --ignore-not-found && kubectl create service app-service --selector version=green

Answer

kubectl set selector service/app-service version=green

Answer

kubectl apply -f service.yaml where service.yaml has the new selector

Question 2

You need to run a batch job that processes a queue and must ensure exactly 5 pods run successfully in parallel. Which Job configuration field should be set?

Accepted Answer

spec.parallelism: 5. `spec.parallelism` controls the maximum number of Pods that can run concurrently for a Job. Setting `parallelism: 5` ensures exactly 5 Pods run in parallel, which matches the requirement to process a queue with five simultaneous workers.

Answer

spec.backoffLimit: 5

Answer

spec.ttlSecondsAfterFinished: 5

Answer

spec.completions: 5

Question 3

A developer needs to deploy a container that runs a batch job to process data once and then exit. The job should be restarted only if it fails. Which Kubernetes resource should be used?

Accepted Answer

Job. A Kubernetes Job is the correct resource for a batch workload that runs to completion and exits. It ensures the pod is restarted only on failure (via the `RestartPolicy: OnFailure` or `Never`), which matches the requirement of restarting only if the job fails. Deployments and DaemonSets are designed for long-running processes, not termination.

Answer

DaemonSet

Answer

Deployment

Answer

StatefulSet

Question 4

Which command creates a ConfigMap named 'app-config' from a file named 'config.properties'?

Accepted Answer

kubectl create configmap app-config --from-file=config.properties. `kubectl create configmap app-config --from-file=config.properties` creates a ConfigMap named `app-config` with a single key `config.properties` (the filename) and the file's entire content as its value. The `--from-file` flag does not parse the file into separate key-value pairs. To parse lines like KEY=VALUE, you would use `--from-env-file`.

Answer

kubectl create configmap app-config --from-env-file=config.properties

Answer

kubectl create configmap app-config --from-literal=config.properties

Answer

kubectl apply configmap app-config --from-file=config.properties

Question 5

An Ingress resource routes traffic to a Service 'web' on port 80. The Service has multiple endpoints but all return 503. What should be checked first?

Accepted Answer

Check the readiness probe of the Pods. A 503 Service Unavailable error from the Ingress indicates the upstream Service is not ready to serve traffic. The most common cause is Pods failing their readiness probes, which removes them from the Service's endpoint list. Checking the readiness probe status directly addresses why the Service has endpoints but returns 503.

Answer

Ensure that the Service type is ClusterIP

Answer

Verify that the Service port matches the Pod's container port

Answer

Check the Ingress controller logs

Question 6

You have a Helm release named 'my-app' that you want to revert to revision 3. Which command accomplishes this?

Accepted Answer

helm rollback my-app 3. The correct command to revert a Helm release to a previous revision is `helm rollback `. In this case, `helm rollback my-app 3` will roll back the 'my-app' release to revision 3, restoring the Kubernetes resources to the state defined in that revision's chart and values.

Answer

helm undo my-app --revision 3

Answer

helm revert my-app 3

Answer

helm upgrade my-app --revision 3

Question 7

Which TWO of the following are valid ways to consume a Secret named 'db-secret' in a Pod? (Choose two.)

Accepted Answer

As environment variables using envFrom with secretRef. `envFrom` with `secretRef` allows a Pod to consume all key-value pairs from a Secret named 'db-secret' as environment variables. This is a standard Kubernetes feature for injecting Secret data into containers without needing to specify each key individually.

Answer

As environment variables using env with valueFrom.configMapKeyRef

Answer

As a command-line argument using $(DB_PASSWORD)

Answer

As an imagePullSecrets entry

Question 8

Which TWO statements about labels and selectors are correct? (Select TWO.)

Accepted Answer

Services use selectors to determine which pods receive traffic.. A is correct because Services use label selectors in their spec.selector field to determine which Pods receive traffic. B is correct because labels are key-value pairs that can be attached to Kubernetes objects for identification and grouping. C is incorrect because selectors return a set of objects matching the given labels, not a single object. D is false because selectors are not required to be defined in the resource definition itself; they are used in controllers and Services to select objects. E is false because labels can be added or modified after creation.

Answer

Selectors are used to identify a single object based on its labels.

Answer

Selectors must be defined in the resource definition itself.

Answer

Labels cannot be added after an object is created.

Question 9

Which TWO of the following are valid non-interactive methods to update a Deployment's image?

Accepted Answer

kubectl replace -f deployment.yaml. Option A (kubectl replace -f deployment.yaml) is correct because replace applies a full manifest non-interactively, so if the YAML file already contains the updated image, the Deployment's Pod template is replaced and a rollout is triggered without opening an editor. Option D (kubectl set image deployment/myapp mycontainer=nginx:1.21) is correct because kubectl set image is a purpose-built, non-interactive command that directly patches the named container's image in the Deployment spec, causing a new ReplicaSet rollout. Option B is not valid here because kubectl edit opens an interactive text editor, which contradicts the non-interactive requirement. Option C is not valid because kubectl rollout does not have an 'image' subcommand; the correct subcommands are status, history, undo, restart, pause, and resume. Option E is not valid because kubectl create fails when the Deployment already exists and is not an update method.

Answer

kubectl edit deployment/myapp and change the image field

Answer

kubectl rollout image deployment/myapp mycontainer=nginx:1.21

Answer

kubectl create -f deployment.yaml

Question 10

A user runs: kubectl run my-pod --image=nginx --restart=Never --dry-run=client -o yaml. Which apiVersion is used in the generated YAML?

Accepted Answer

v1. The `kubectl run` command, when used with `--restart=Never`, creates a standalone Pod. Pods are the most basic Kubernetes resource and belong to the core API group, which uses the `v1` apiVersion (i.e., `apiVersion: v1`). Options like `apps/v1` or `batch/v1` are for higher-level controllers such as Deployments or Jobs, not for a direct Pod creation.

Answer

apps/v1

Answer

batch/v1

Answer

networking.k8s.io/v1