This KCNA practice question tests your understanding of kubernetes fundamentals. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
You need to expose a set of pods running in the 'dev' namespace internally within the cluster on a stable IP. All pods have the label 'app: web'. Which kubectl command should you use?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
kubectl expose deployment web --port=80 --target-port=8080 --name=web-service -n dev
Option A is correct because it exposes the existing deployment named 'web' (which manages pods with label 'app: web') as a ClusterIP service, providing a stable internal IP and DNS name within the cluster. The `--port=80` sets the service port, and `--target-port=8080` maps to the container port, ensuring traffic reaches the pods correctly in the 'dev' namespace.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✓
kubectl expose deployment web --port=80 --target-port=8080 --name=web-service -n dev
Why this is correct
If the pods are managed by a Deployment named 'web', this creates a Service that targets the pods.
Related concept
Read the scenario before looking for a memorised answer.
✗
kubectl create service clusterip web --tcp=80:8080 -n dev
Why it's wrong here
This command creates a Service but requires manual selector specification; using `kubectl expose` is more direct for existing pods.
✗
kubectl run web --image=nginx --port=80 -n dev
Why it's wrong here
This creates a pod, not a Service.
✗
kubectl expose pod web --port=80 --target-port=8080 --name=web-service -n dev
Why it's wrong here
This command is for a single pod, not a set of pods.
Common exam traps
Common exam trap: answer the scenario, not the keyword
CNCF often tests the distinction between exposing a deployment (which uses a label selector for all pods) versus exposing a specific pod (which targets only that pod by name), leading candidates to choose Option D incorrectly.
Trap categories for this question
Command / output trap
This command creates a Service but requires manual selector specification; using `kubectl expose` is more direct for existing pods.
Detailed technical explanation
How to think about this question
The `kubectl expose deployment` command automatically uses the deployment's label selector (e.g., 'app: web') to create a ClusterIP service, which assigns a stable virtual IP from the cluster's service CIDR range. This service uses iptables or IPVS rules to load-balance traffic across all matching pods, and the service DNS name (e.g., 'web-service.dev.svc.cluster.local') resolves to that IP. In real-world scenarios, this ensures that even if pods are recreated or scaled, clients always reach the service via the same IP.
KKey Concepts to Remember
Read the scenario before looking for a memorised answer.
Find the constraint that changes the correct option.
Eliminate answers that are true in general but not in this case.
TExam Day Tips
→Watch for words such as best, first, most likely and least administrative effort.
→Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A practitioner preparing for the KCNA exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this KCNA question in full detail.
Kubernetes Fundamentals — This question tests Kubernetes Fundamentals — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: kubectl expose deployment web --port=80 --target-port=8080 --name=web-service -n dev — Option A is correct because it exposes the existing deployment named 'web' (which manages pods with label 'app: web') as a ClusterIP service, providing a stable internal IP and DNS name within the cluster. The `--port=80` sets the service port, and `--target-port=8080` maps to the container port, ensuring traffic reaches the pods correctly in the 'dev' namespace.
What should I do if I get this KCNA question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
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.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.