KCNA Practice Test 2 — 10 Questions

Question 1

Which TWO of the following are CNCF graduated projects? (Select 2)

Accepted Answer

Prometheus. Prometheus and Envoy are both CNCF graduated projects. CoreDNS is also graduated, but the question asks for two; Fluentd and Helm are both graduated as well, but the correct answers here are Prometheus and Envoy.

Answer

Kyverno

Answer

Knative

Answer

ArgoCD

Question 2

Which command would you use to apply a manifest file 'deployment.yaml' to a Kubernetes cluster?

Accepted Answer

kubectl apply -f deployment.yaml. The 'kubectl apply' command is used to apply or update resources from a manifest file.

Answer

kubectl run deployment.yaml

Answer

kubectl set image deployment.yaml

Answer

kubectl create -f deployment.yaml

Question 3

Which of the following is a key principle of the 12-factor app methodology related to managing configuration?

Accepted Answer

Use environment variables for configuration. The 12-factor app methodology states that configuration should be stored in environment variables (or external to the code) to vary between deployments without changing code. Hardcoding is the opposite. ConfigMaps are Kubernetes-specific but the principle is broader. Secrets are for sensitive data but not the only way.

Answer

Store configuration in the application code

Answer

Embed configuration in the build process

Answer

Use a configuration file in the application directory

Question 4

In a service mesh architecture, which component is responsible for intercepting and managing traffic between microservices?

Accepted Answer

Sidecar proxy. The sidecar proxy (usually Envoy) is deployed alongside each service instance and handles all incoming and outgoing traffic, enabling observability, traffic management, and security. The control plane manages configuration but does not handle data plane traffic. The API gateway is a separate component for external traffic. The service registry is a pattern but not a specific service mesh component.

Answer

Control plane

Answer

API gateway

Answer

Service registry

Question 5

Which GitOps tool is a CNCF graduated project that synchronizes Kubernetes clusters with a Git repository?

Accepted Answer

Argo CD. Argo CD is a CNCF graduated project for GitOps on Kubernetes.

Answer

Tekton

Answer

Jenkins X

Answer

Flux

Question 6

A pod is in CrashLoopBackOff state. 'kubectl logs pod' shows 'Error: cannot connect to database at db-service:5432'. The database Service exists and is reachable from other pods. What is the most likely cause?

Accepted Answer

The application's configuration has incorrect database connection details. The error indicates the application cannot connect to the database. Since other pods can reach the database, the issue is specific to this pod. A common cause is that the pod's configuration (e.g., environment variables, config file) contains wrong connection details, such as incorrect service name, port, or credentials.

Answer

The kube-proxy is not functioning

Answer

The pod's resource limits are too low

Answer

The database pod is not running

Question 7

What is the primary purpose of the CNCF (Cloud Native Computing Foundation)?

Accepted Answer

To host and support open-source cloud-native projects. The CNCF hosts, supports, and sustains open-source cloud-native projects, ensuring they are vendor-neutral and fostering community collaboration. It does not develop projects itself but provides a governance model.

Answer

To develop proprietary cloud software

Answer

To define cloud-native standards only

Answer

To certify cloud providers

Question 8

Which component in an event-driven architecture is responsible for decoupling event producers from consumers?

Accepted Answer

Event broker. An event broker (or message broker) acts as an intermediary that receives events from producers and delivers them to consumers, allowing loose coupling. The API gateway handles synchronous requests. The service mesh handles service-to-service communication. The config server manages configuration.

Answer

Config server

Answer

API gateway

Answer

Service mesh

Question 9

Which THREE of the following are true about the Open Container Initiative (OCI)? (Choose 3)

Accepted Answer

OCI defines both an image spec and a runtime spec. The OCI defines the image spec and runtime spec, ensuring interoperability between container tools. containerd is an OCI-compliant runtime. Docker images are OCI-compliant. Docker itself is not a runtime spec but a platform that uses runtimes.

Answer

Docker is an OCI runtime specification

Answer

OCI is governed by the Cloud Native Computing Foundation (CNCF)