EX280 Storage And Persistent Volumes Practice Test 2 — 15 Questions

Question 1

Which THREE actions occur when a PersistentVolumeClaim with reclaimPolicy: Delete is deleted by a user?

Accepted Answer

The physical storage asset on the storage backend is deleted.. Option E is correct because deleting a PersistentVolumeClaim object simply removes that PVC resource from its namespace, which is the user-initiated action that triggers the rest of the reclaim workflow. Option B is correct because once the PVC is gone and the PV's reclaim policy is Delete, the dynamic provisioner deletes the associated PersistentVolume object from the cluster rather than leaving it in a Released state. Option A is correct because the Delete reclaim policy instructs the provisioner to also delete the underlying physical storage asset on the storage backend (for example, an AWS EBS volume, GCE PD, or Cinder volume) after the PV object is removed. Option D is wrong because Released-and-retained behavior describes the Retain reclaim policy, not Delete. Option C is wrong because Kubernetes' Delete reclaim policy does not create immutable snapshots; snapshotting requires separate VolumeSnapshot resources and is not an automatic part of PVC deletion.

Answer

The storage backend archives the data into an immutable snapshot.

Answer

The PV status changes to Released and remains indefinitely.

Question 2

Which THREE tasks must an administrator perform to enable volume snapshots in an OpenShift cluster using a CSI driver that supports snapshots?

Accepted Answer

Deploy the Volume Snapshot Controller (if not managed by the CSI operator).. Enabling snapshots requires installing the Volume Snapshot CRDs, deploying the external snapshot controller operator/controller, and creating a VolumeSnapshotClass.

Answer

Format all worker nodes with XFS filesystems.

Question 3

A developer needs to restore a previously captured VolumeSnapshot into a new PersistentVolumeClaim to revert application state. What key field must be specified in the new PVC definition to initiate the restore operation from the snapshot?

Accepted Answer

spec.dataSource referencing the VolumeSnapshot. The correct field is spec.dataSource, which is a Kubernetes PersistentVolumeClaim API field that allows specifying a VolumeSnapshot as the source for provisioning a new volume. When a PVC includes spec.dataSource with kind: VolumeSnapshot, apiGroup: snapshot.storage.k8s.io, and name set to the snapshot, the CSI driver triggers a restore operation, creating a new volume populated with the snapshot's data. This is the standard mechanism defined by the Kubernetes CSI snapshot feature, and it requires the VolumeSnapshotClass and VolumeSnapshotContent to be properly configured.

Answer

metadata.annotations['snapshot.storage.kubernetes.io/restore']

Answer

spec.resources.requests.storage matching the exact snapshot block ID

Answer

spec.volumeName matching the UUID of the snapshot storage backend

Question 4

An administrator creates a PersistentVolumeClaim that requests 5Gi with accessMode ReadWriteOnce. The cluster has two matching PersistentVolumes available: pv-a with 10Gi and accessMode ReadWriteOnce, and pv-b with 5Gi and accessMode ReadWriteMany. Both have reclaim policy Retain. Which PersistentVolume will be bound to the claim, and why?

Accepted Answer

pv-b, because it exactly matches the requested capacity and supports ReadWriteOnce.. The PersistentVolume controller binds a claim to the smallest volume that meets or exceeds the requested capacity and whose access modes are a superset of the claim's. The volume with exact capacity and compatible access mode is selected. Volumes that are larger are considered only if no smaller match exists. This ensures efficient use of storage resources.

Answer

Neither volume will bind because the access modes do not match exactly.

Answer

pv-a, because it is the first matching volume in alphabetical order.

Answer

pv-a, because it has the larger capacity and can accommodate future growth.

Question 5

A StatefulSet named 'db' with three replicas uses volumeClaimTemplates to provision storage. An administrator needs to verify that each replica's PersistentVolumeClaim was created with the correct storage class and capacity. Which command should the administrator run to list only the PVCs belonging to this StatefulSet?

Accepted Answer

oc get pvc -n <namespace>. StatefulSet volumeClaimTemplates create one PVC per replica, named by concatenating the template name, the StatefulSet name, and the ordinal index. Because these PVCs are not labeled with the StatefulSet's pod labels, filtering by label or exact name fails. Listing all PVCs in the namespace exposes each generated claim with its real storage class and capacity.

Answer

oc get pvc -n <namespace> -l app=db

Answer

oc describe statefulset db -n <namespace>

Answer

oc get pvc -n <namespace> --field-selector metadata.name=db

Question 6

An administrator creates a PersistentVolumeClaim with storageClassName: fast-ssd, but the claim remains Pending indefinitely. The StorageClass fast-ssd exists and its provisioner is csi.example.com. The cluster's default StorageClass is standard. Which action should the administrator take first to diagnose why the PVC is not being provisioned?

Accepted Answer

Run oc get storageclass fast-ssd -o yaml and check whether volumeBindingMode is set to WaitForFirstConsumer.. With volumeBindingMode: WaitForFirstConsumer, the provisioner waits until a pod using the PVC is scheduled, so the claim stays Pending when no consumer exists. Inspecting the StorageClass YAML confirms this mode. Checking the default class, recreating the class, or probing the CSI driver all overlook the intended delayed-binding behavior.

Answer

Run oc describe pvc and look for an event stating that the default StorageClass standard is missing.

Answer

Delete and recreate the StorageClass fast-ssd to force the provisioner to retry.

Answer

Check whether the CSI driver pod csi.example.com is running in the openshift-storage namespace.

Question 7

A stateful application needs its PersistentVolume to be bound only after the pod requesting it is assigned to a specific worker node, to avoid topology mismatch issues. Which StorageClass parameter achieves this?

Accepted Answer

volumeBindingMode: WaitForFirstConsumer. The volumeBindingMode: WaitForFirstConsumer parameter in a StorageClass delays volume binding until a pod using the PVC is scheduled. This ensures that the PersistentVolume is provisioned in the same topology zone as the node where the pod runs, preventing topology mismatch. It is the correct setting for stateful applications that require node-local or zone-specific storage.

Answer

allowVolumeExpansion: true

Answer

volumeBindingMode: Immediate

Answer

bindingMode: Late

Question 8

You need to provide temporary scratch space for a container that shares the pod's lifetime and is cleared when the pod is deleted. Which volume type should you configure in the Pod specification?

Accepted Answer

emptyDir. An emptyDir volume is created when a pod is assigned to a node and exists for the lifetime of that pod. It is initially empty, provides scratch space for the container, and is deleted permanently when the pod is removed from the node. This exactly matches the requirement for temporary, pod-lifetime scratch space.

Answer

persistentVolumeClaim

Answer

hostPath

Answer

nfs

Question 9

An administrator needs to increase the size of an existing PVC bound to a gp3 storage class in an OpenShift cluster. What is the mandatory first step before editing the PVC spec?

Accepted Answer

Ensure allowVolumeExpansion: true is set on the corresponding StorageClass.. Before a PVC can be expanded, the StorageClass that provisioned it must have 'allowVolumeExpansion: true' set. Without this field, the PVC's spec.resources.requests.storage cannot be increased — the API server will reject the edit or the resize will never complete. This is the mandatory first step.

Answer

Manually update the underlying cloud provider disk size via the AWS console.

Answer

Delete the PV and recreate it with the new size.

Answer

Scale down all pods using the PVC to zero replicas.

Question 10

A cluster administrator wants to create a VolumeSnapshot of a database PVC. Which API group must the VolumeSnapshotClass belong to?

Accepted Answer

snapshot.storage.k8s.io. VolumeSnapshotClass resources are part of the Kubernetes CSI snapshot API group 'snapshot.storage.k8s.io'. This API group defines the VolumeSnapshot, VolumeSnapshotContent, and VolumeSnapshotClass custom resources. Therefore, the VolumeSnapshotClass must belong to this API group to be recognized by the CSI snapshot controller.

Answer

storage.k8s.io

Answer

csi.storage.k8s.io

Answer

volumesnapshot.openshift.io

Question 11

You want to restore an existing VolumeSnapshot into a new PersistentVolumeClaim. Which field in the PVC specification must reference the VolumeSnapshot?

Accepted Answer

dataSource. In Kubernetes/OpenShift, restoring a VolumeSnapshot into a new PVC is done by setting the PVC's spec.dataSource field to reference the VolumeSnapshot object (apiGroup: snapshot.storage.k8s.io, kind: VolumeSnapshot, name: <snapshot-name>). This tells the CSI provisioner to create the new volume from the snapshot's contents rather than provisioning an empty volume. The dataSource field is the standard, GA mechanism for both snapshot restore and volume cloning.

Answer

claimRef

Answer

snapshotName

Answer

volumeName

Question 12

A cluster administrator notices that a PVC stuck in the Pending state references a StorageClass with volumeBindingMode set to WaitForFirstConsumer. What action will cause the PVC to bind?

Accepted Answer

Create and schedule a Pod that mounts the PVC.. With volumeBindingMode: WaitForFirstConsumer, the storage provisioner delays binding until a pod using the PVC is scheduled, allowing the scheduler to pick a node and then provision storage in the correct topology zone. Creating and scheduling a pod that mounts the PVC triggers the provisioning and binding process. Until such a pod exists, the PVC remains Pending by design.

Answer

Delete the StorageClass and recreate it with Immediate binding mode.

Answer

Restart the kube-apiserver service on the control plane nodes.

Answer

Manually create a PV matching the exact size and labels of the PVC.

Question 13

An administrator needs to inspect all StorageClasses available in an OpenShift cluster using the OpenShift CLI. Which command should be executed?

Accepted Answer

oc get sc. The command 'oc get sc' is the correct and concise way to list all StorageClasses in an OpenShift cluster. 'sc' is the standard abbreviation for 'storageclasses' in the OpenShift CLI, and 'oc get' retrieves the list of resources. This command provides a quick overview of available StorageClasses, which is essential for administrators managing persistent storage.

Answer

oc describe storageclasses

Answer

oc get pvc

Answer

oc get pv

Question 14

An OpenShift cluster uses a CSI driver that supports volume cloning. A user wants to clone an existing PVC named 'data-pvc' into a new PVC named 'clone-pvc'. How should the dataSource be specified?

Accepted Answer

dataSource: { apiGroup: "", kind: "PersistentVolumeClaim", name: "data-pvc" }. To clone an existing PVC named 'data-pvc' into a new PVC named 'clone-pvc' using a CSI driver that supports volume cloning, the dataSource field must specify the source PVC. The correct specification is dataSource: { apiGroup: "", kind: "PersistentVolumeClaim", name: "data-pvc" }. The apiGroup is empty because PersistentVolumeClaim is a core Kubernetes resource. This tells the CSI driver to clone the volume from the specified PVC.

Answer

dataSource: { apiGroup: "snapshot.storage.k8s.io", kind: "VolumeSnapshot", name: "data-pvc" }

Answer

spec.cloneSource: "data-pvc"

Answer

spec.volumeName: "data-pvc"

Question 15

A developer deploys a pod with an emptyDir volume. The application running inside writes temporary files. What happens to these files when the container crashes and restarts within the same pod?

Accepted Answer

The files are preserved because emptyDir lifetime is tied to the pod, not individual containers.. An emptyDir volume in Kubernetes is created when a pod is assigned to a node and exists for the lifetime of that pod. If a container within the pod crashes and restarts, the emptyDir volume and its data persist because the pod itself has not been deleted. The files are preserved as long as the pod remains on the node.

Answer

The files are backed up to the cluster control plane automatically.

Answer

The files are deleted immediately because the container filesystem is ephemeral.

Answer

The volume is unmounted and reattached via the CSI driver.