KCNA Kubernetes Fundamentals Practice Test 11 — 15 Questions

Question 1

You create a Service of type NodePort with nodePort: 30080. The cluster's nodes have IP addresses 10.0.0.1 and 10.0.0.2. From outside the cluster, which address and port can you use to access the Service?

Accepted Answer

10.0.0.1:30080. NodePort exposes the service on each node's IP at the specified nodePort (30080). The service is reachable via :. The internal ClusterIP is not reachable externally unless using a proxy or Ingress.

Answer

10.0.0.1:80

Answer

ClusterIP:80

Answer

10.0.0.2:8080

Question 2

Which two components are part of the Kubernetes worker node? (Select TWO)

Accepted Answer

kubelet. Kubelet and container runtime are essential components running on each worker node. Kube-proxy also runs on worker nodes but is often considered part of the node. The question asks for two, and the most fundamental are kubelet and container runtime.

Answer

kube-controller-manager

Answer

etcd

Answer

kube-scheduler

Question 3

Which three of the following are valid methods to expose a Service to external traffic? (Select THREE)

Accepted Answer

Ingress. NodePort, LoadBalancer, and Ingress are all valid methods to expose services externally. ClusterIP only exposes internally within the cluster.

Answer

ClusterIP

Answer

ExternalName

Question 4

Which two of the following are Kubernetes controllers that run inside the kube-controller-manager? (Select TWO)

Accepted Answer

Replication controller. Node controller and Replication controller are part of the controller-manager. The scheduler is a separate component. kubelet is a node agent, not a controller.

Answer

kubelet

Answer

etcd

Answer

kube-scheduler

Question 5

Which component is the primary entry point for all administrative tasks and API requests in a Kubernetes cluster?

Accepted Answer

kube-apiserver. The kube-apiserver is the front-end of the Kubernetes control plane and exposes the Kubernetes API.

Answer

kube-controller-manager

Answer

etcd

Answer

kube-scheduler

Question 6

What is the purpose of a Kubernetes Service?

Accepted Answer

To provide a stable endpoint for a set of pods. A Service provides a stable IP address and DNS name to access a set of pods, enabling load balancing and service discovery.

Answer

To store configuration data as key-value pairs

Answer

To manage rolling updates of container images

Answer

To schedule pods onto nodes

Question 7

A developer needs to deploy a stateless application with three replicas and ensure that updates are rolled out with zero downtime. Which Kubernetes resource is most appropriate?

Accepted Answer

Deployment. A Deployment manages ReplicaSets and supports declarative rolling updates, making it ideal for stateless applications.

Answer

StatefulSet

Answer

Job

Answer

DaemonSet

Question 8

You run 'kubectl get pods' and see a pod with status 'Pending'. Which is the most likely cause?

Accepted Answer

The scheduler cannot find a node that meets the pod's resource requirements. A Pending pod usually indicates scheduling issues, such as insufficient resources or node constraints.

Answer

The pod's container has crashed

Answer

The container image is not found

Answer

The pod has been deleted by a controller

Question 9

Which command creates a Deployment named 'nginx-deployment' from the image 'nginx:1.25' and exposes it on port 80?

Accepted Answer

kubectl create deployment nginx-deployment --image=nginx:1.25 --port=80. The 'kubectl create deployment' command creates a Deployment, and '--expose' also creates a Service.

Answer

kubectl run nginx-deployment --image=nginx:1.25 --port=80

Answer

kubectl apply -f nginx-deployment.yaml

Answer

kubectl expose deployment nginx-deployment --type=ClusterIP

Question 10

A pod is running a Java application that occasionally leaks memory. After a few hours, 'kubectl describe pod' shows the container exited with OOMKilled. You want to automatically restart the container but ensure the application has enough memory. What should you do?

Accepted Answer

Increase the memory limit in the container's resources.limits and add a liveness probe that triggers on high memory usage. The default restart policy is Always, so the container will restart. The solution is to increase the memory limit and consider using a liveness probe to detect and restart earlier.

Answer

Set restartPolicy: OnFailure in the pod spec

Answer

Use a DaemonSet instead of a Deployment

Answer

Set terminationGracePeriodSeconds to 0

Question 11

Which component runs on every Kubernetes node and ensures that the containers in a pod are running?

Accepted Answer

kubelet. The kubelet is the primary node agent that watches for pod specs and ensures the containers are healthy.

Answer

kube-proxy

Answer

kube-scheduler

Answer

container runtime

Question 12

You want to view the logs of a running pod named 'my-pod'. Which kubectl command should you use?

Accepted Answer

kubectl logs my-pod. kubectl logs <pod-name> fetches logs from the container(s) in the pod.

Answer

kubectl exec my-pod -- cat /var/log/container.log

Answer

kubectl get pod my-pod -o yaml

Answer

kubectl describe pod my-pod

Question 13

A Kubernetes cluster has multiple worker nodes. You create a Pod without any node selector. The scheduler places the pod on a node, but the pod remains in 'Pending' state. 'kubectl describe pod' shows '0/1 nodes are available: 1 node had taint {node-role.kubernetes.io/master: }, that the pod didn't tolerate'. What does this indicate?

Accepted Answer

The node has a taint that the pod does not tolerate. The node is tainted, and the pod lacks the corresponding toleration. The scheduler cannot schedule the pod on that node.

Answer

The pod has a resource request that exceeds the node's capacity

Answer

The node is cordoned and should be uncordoned

Answer

The node is out of disk space

Question 14

Which Kubernetes object can be used to store sensitive data, such as passwords or API keys, and inject them into pods?

Accepted Answer

Secret. Secrets are designed to store sensitive information and can be mounted as volumes or environment variables.

Answer

PersistentVolume

Answer

ServiceAccount

Answer

ConfigMap

Question 15

You create a Service of type ClusterIP in the 'default' namespace. You try to reach the Service from a pod in the 'production' namespace using the service name. The connection fails. What is the most likely reason?

Accepted Answer

The pod cannot resolve the DNS name because service DNS names are only resolvable within the same namespace. Service DNS names are scoped to namespaces. To access a service in another namespace, you must use the fully qualified name: ..svc.cluster.local.

Answer

Cross-namespace service access is not allowed by default

Answer

The service has no endpoints

Answer

The service port is not correctly configured