CKA Workloads and Scheduling Practice Test 6 — 15 Questions

Question 1

Which TWO of the following are valid ways to expose a ConfigMap to a pod? (Select TWO)

Accepted Answer

Mounting the ConfigMap as a volume. A ConfigMap can be mounted as a volume in a Pod, allowing files to be created in the container's filesystem from the ConfigMap's data. This is done by defining a volume of type `configMap` in the Pod spec and mounting it at a desired path, such as `/etc/config`. The mount makes each key in the ConfigMap become a file, with the key as the filename and the value as the file content. Additionally, specific keys from a ConfigMap can be injected as environment variables using `configMapKeyRef` in the container's environment definition, allowing the Pod to consume ConfigMap data as env vars.

Answer

The ConfigMap is automatically mounted at /etc/config in the container

Answer

Using the ConfigMap as a container image

Answer

The ConfigMap is automatically available as environment variables in the pod

Question 2

Which THREE of the following are characteristics of a Kubernetes StatefulSet? (Select THREE)

Accepted Answer

Pods are created and terminated in a predictable order (ordinal index). StatefulSets assign each pod a stable, unique network identity (hostname) based on its ordinal index, and pods are created and terminated in a a predictable order (from 0 to N-1). This ordered behavior is essential for applications like databases that require a fixed startup sequence.

Answer

Pods are created in random order

Answer

All pods in the StatefulSet are interchangeable

Question 3

Which TWO of the following are true about a HorizontalPodAutoscaler (HPA) using average CPU utilization? (Select TWO)

Accepted Answer

The HPA calculates utilization as the average CPU usage across all pods divided by the CPU request per pod. The HorizontalPodAutoscaler (HPA) calculates the average CPU utilization across all pods as the sum of CPU usage (from the metrics server) divided by the sum of CPU requests. This average is then compared to the target percentage. The formula is: (total CPU usage across pods) / (total CPU requests across pods) * 100, which yields a percentage that the HPA uses to decide scaling actions.

Answer

The HPA target is an absolute CPU value, not a percentage

Answer

If the average CPU utilization exceeds the target, the HPA will scale down

Answer

The HPA uses CPU limits in its calculation of average utilization

Question 4

A StatefulSet named 'db' manages 3 pods. The pods are named db-0, db-1, db-2. What is the expected behavior when the StatefulSet's pod management policy is set to OrderedReady and you scale down from 3 to 1 replica?

Accepted Answer

Pod db-2 is deleted, then db-1, and db-0 remains.. With the OrderedReady pod management policy, scaling down a StatefulSet deletes pods in reverse ordinal order, starting from the highest index. When scaling from 3 to 1 replica, pods db-2 (index 2) is deleted first, then db-1 (index 1), leaving db-0 (index 0) running. This ensures that each pod is fully terminated before the next one is deleted, maintaining the ordered startup and shutdown guarantees.

Answer

All pods are deleted simultaneously.

Answer

Only pod db-2 is deleted; db-1 and db-0 remain.

Answer

Pod db-0 is deleted first, then db-1, and db-2 remains.

Question 5

You have a DaemonSet that runs a logging agent on all nodes. You want to update the agent's image to a new version. Which update strategy allows you to control the rollout by manually updating each node's DaemonSet pod?

Accepted Answer

OnDelete. The DaemonSet's OnDelete update strategy requires you to manually delete each DaemonSet pod to trigger its recreation with the new image. This gives you explicit, per-node control over the rollout, which matches the requirement of manually updating each node's pod.

Answer

BlueGreen

Answer

Recreate

Answer

RollingUpdate with maxUnavailable: 0

Question 6

A pod is stuck in Pending state. You run 'kubectl describe pod my-pod' and see the event: '0/4 nodes are available: 1 node(s) had taint {gpu: true} that the pod didn't tolerate, 3 node(s) had resource pressure.'. What is the most likely cause?

Accepted Answer

The pod needs a toleration for the gpu taint, and nodes have resource constraints.. The event message explicitly states that 1 node has a taint (gpu: true) that the pod does not tolerate, and 3 nodes have resource pressure (e.g., memory, disk, or PID exhaustion). A pod remains in Pending state when no node can satisfy its scheduling requirements; adding a toleration for the gpu taint would allow scheduling on that node, but the resource pressure on the other nodes must also be resolved (e.g., by freeing resources or increasing capacity).

Answer

The pod has a nodeSelector that doesn't match any node.

Answer

The pod is using a deprecated API version.

Answer

The pod's image pull secret is missing.

Question 7

Which command retrieves the rollout history of a Deployment named 'web'?

Accepted Answer

kubectl rollout history deployment web. The `kubectl rollout history deployment web` command retrieves the revision history of the specified Deployment, showing each revision number and, with the `--revision` flag, the details of a specific revision. This is the standard Kubernetes command for viewing rollout history, as defined in the kubectl reference.

Answer

kubectl describe deployment web

Answer

kubectl get events --field-selector involvedObject.name=web

Answer

kubectl rollout status deployment web

Question 8

You need to schedule a pod on a node with label 'disktype=ssd'. Which field should you add to the pod spec?

Accepted Answer

nodeSelector. The `nodeSelector` field in a Pod spec is the simplest and most direct way to constrain a Pod to nodes that have a specific label. By setting `nodeSelector` with `disktype: ssd`, the scheduler will only consider nodes that have the label `disktype=ssd` for placement. This is a hard constraint that does not require any additional configuration on the nodes.

Answer

tolerations

Answer

nodeName

Answer

affinity.nodeAffinity

Question 9

Which ONE of the following is a valid field in a PodSpec for defining init containers?

Accepted Answer

initContainers. The `initContainers` field in the PodSpec is used to define init containers. The other options are separate PodSpec fields with different purposes: `volumes` for storage, `imagePullSecrets` for pulling private images, `restartPolicy` is a PodSpec field for restart behavior (not for defining init containers), and `containers` is for main application containers, not init containers.

Answer

volumes

Answer

imagePullSecrets

Answer

restartPolicy

Answer

containers

Question 10

Which TWO taint effects can be used to prevent a pod from being scheduled on a node unless it has a matching toleration?

Accepted Answer

NoExecute. Taints and tolerations in Kubernetes control which pods can be scheduled onto nodes. The `NoSchedule` taint effect prevents scheduling of pods that do not tolerate it, while `NoExecute` evicts existing pods and prevents new scheduling unless tolerated. Both effects ensure pods without matching tolerations are not scheduled on the node.

Answer

PreferNoSchedule

Answer

FailSchedule

Answer

NoAdmit

Question 11

Which TWO of the following are valid methods to expose ConfigMap data to pods?

Accepted Answer

As environment variables. ConfigMap data can be injected into a pod as environment variables using the `envFrom` or `env` field in the pod spec, referencing the ConfigMap name and keys. This allows the pod to consume configuration values as standard environment variables, which are accessible to the container runtime at process startup.

Answer

As a Kubernetes Service

Answer

As a container command argument

Answer

As a Pod annotation

Question 12

Which THREE of the following are true about pod lifecycle phases?

Accepted Answer

A pod in Pending phase may have init containers still running.. The Kubernetes pod lifecycle has five phases: Pending, Running, Succeeded, Failed, and Unknown. Running means the pod has been bound to a node and all containers have been created, but at least one container is still running or starting/restarting; it does not require that all containers are running. Failed means all containers have terminated, with at least one having a non-zero exit code, not necessarily all. Therefore, A and D are incorrect. Pending can indeed include init containers still running, so E is correct.

Answer

Running phase means all containers are running.

Answer

CrashLoopBackOff is a pod phase.

Answer

Terminating is a pod phase during graceful shutdown.

Answer

Failed phase indicates all containers have terminated with a non-zero exit code.

Question 13

A pod in the 'production' namespace is in a CrashLoopBackOff state. The pod has been running successfully for several days. You run 'kubectl describe pod app-pod -n production' and see the message: 'OOMKilled'. What is the MOST appropriate action to resolve this issue?

Accepted Answer

Increase the memory limit in the pod's container resource specification. The 'OOMKilled' status indicates the container was terminated because it exceeded its memory limit. Since the pod ran successfully for days, the issue is likely a memory leak or increased workload demand. Increasing the memory limit in the container's resource specification allows the pod to handle the higher memory usage without being killed.

Answer

Delete the namespace and redeploy all workloads

Answer

Delete and recreate the pod to clear the crash loop

Answer

Increase the CPU request for the container

Question 14

Which kubectl command will show the rollout history of a Deployment named 'web-app'?

Accepted Answer

kubectl rollout history deployment web-app. `kubectl rollout history deployment web-app` is the dedicated command to display the rollout history of a Deployment, including revision numbers and change-cause annotations. This command retrieves the stored ReplicaSet revisions associated with the Deployment, allowing you to see past rollout states.

Answer

kubectl describe deployment web-app

Answer

kubectl rollout status deployment web-app

Answer

kubectl get deployment web-app -o yaml

Question 15

You have a Deployment 'db' with 3 replicas. Each pod writes to a PersistentVolumeClaim (PVC). A StatefulSet is required for stable network identities and ordered pod management. Which of the following is a key characteristic that differentiates a StatefulSet from a Deployment?

Accepted Answer

StatefulSets maintain a sticky identity for each pod, including stable hostnames and persistent storage. StatefulSets assign each pod a unique, stable network identity (e.g., a hostname derived from the StatefulSet name and ordinal index) and guarantee that each pod's PersistentVolumeClaim is bound to the same PersistentVolume across rescheduling. This ensures that each pod retains its identity and data, which is critical for stateful applications like databases. Deployments, in contrast, treat pods as interchangeable and do not guarantee stable hostnames or persistent storage binding.

Answer

StatefulSets support rolling updates but not canary deployments

Answer

StatefulSets automatically create a Service for each pod

Answer

StatefulSets cannot use PersistentVolumeClaims