KCNA Container Orchestration Practice Question
Your organization runs a microservices application in a Kubernetes cluster with 5 worker nodes. Each microservice is deployed as a Deployment with 3 replicas. Recently, users report intermittent timeouts when accessing the frontend service. The frontend communicates with a backend service via ClusterIP. You check the backend pods and find that one of the three replicas is in CrashLoopBackOff. The other two backend pods are healthy. The frontend deployment has no readiness or liveness probes. You notice that the frontend's connection pool to the backend has a timeout of 5 seconds. The crashing backend pod logs show an occasional NullPointerException that causes the container to restart, but the pod becomes ready after restart within 2 seconds. However, the frontend's connection pool does not evict unhealthy connections quickly. What is the best course of action to reduce timeouts?
⚠ Common exam trap
Watch out — candidates often confuse readiness and liveness probes, thinking a liveness probe is needed to restart the failing backend pod, but the real issue is traffic routing and connection pool management, which a readiness probe solves by removing the unhealthy pod from the service endpoints.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Add a readiness probe to the backend Deployment that checks the application health endpoint.
The intermittent timeouts occur because the frontend's connection pool holds stale connections to the backend pod that is in CrashLoopBackOff. Although the pod restarts and becomes ready within 2 seconds, the frontend does not detect that the old connection is broken and continues to use it until the 5-second timeout expires. Adding a readiness probe to the backend Deployment ensures that Kubernetes only sends traffic to pods that pass the health check; when the pod fails the probe, it is removed from the ClusterIP's endpoints, preventing the frontend from routing requests to it and thus eliminating the timeouts.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Increase the number of backend replicas to 5 to absorb the failures.
Why it's wrong here
More replicas may reduce impact but not eliminate timeouts if traffic still hits the unhealthy pod.
- ✓
Add a readiness probe to the backend Deployment that checks the application health endpoint.
Why this is correct
Readiness probe will remove the pod from the Service endpoints when it is not ready.
- ✗
Add a liveness probe to the frontend Deployment.
Why it's wrong here
Liveness probe restarts frontend pods, which does not address backend issues.
- ✗
Increase the frontend connection pool timeout to 10 seconds.
Why it's wrong here
Longer timeout may reduce timeouts but does not prevent traffic to unhealthy backend.
Go deeper
Related to this question
About these practice questions
One of 833 original KCNA practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This KCNA practice question is part of Courseiva's free CNCF certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the KCNA exam.