This CKA practice question tests your understanding of workloads & scheduling. This is a configuration task: choose the command set that satisfies every stated requirement. Small differences — like 'secret' vs 'password' or 'transport input ssh' vs 'all' — change whether the answer is correct. 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 are managing a production Kubernetes cluster with 10 worker nodes. A critical application runs as a Deployment with 5 replicas. The application requires low latency inter-Pod communication, so you want to ensure that all replicas are scheduled on the same node to avoid network overhead. You have created a podAntiAffinity rule with requiredDuringSchedulingIgnoredDuringExecution for the app label, but the scheduler only places 1 replica per node, resulting in Pods being distributed across multiple nodes. You need to modify the configuration so that all replicas are placed on a single node, if possible. Which action should you take?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Replace podAntiAffinity with podAffinity using requiredDuringSchedulingIgnoredDuringExecution for the app label.
Option A is correct because podAffinity with requiredDuringSchedulingIgnoredDuringExecution forces the scheduler to co-locate all Pods with the same app label on the same node. This directly overrides the default anti-affinity behavior that spreads Pods across nodes, ensuring low-latency inter-Pod communication by placing all replicas on a single node if possible.
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.
✓
Replace podAntiAffinity with podAffinity using requiredDuringSchedulingIgnoredDuringExecution for the app label.
Why this is correct
PodAffinity attracts Pods to nodes that already have Pods with matching labels, ensuring all replicas on the same node.
Related concept
Read the scenario before looking for a memorised answer.
✗
Create a ResourceQuota to limit the number of Pods per namespace.
Why it's wrong here
ResourceQuota does not control scheduling placement.
✗
Add a toleration for a taint that is present on only one node.
Why it's wrong here
Tolerations allow scheduling on tainted nodes, but do not force colocation.
✗
Add a nodeSelector to the Pod spec to select a specific node.
Why it's wrong here
NodeSelector does not ensure all replicas on the same node; it only restricts eligible nodes.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates confuse podAntiAffinity (which spreads Pods) with podAffinity (which co-locates Pods), and mistakenly think modifying the anti-affinity rule or using nodeSelector will achieve co-location, when only podAffinity with requiredDuringSchedulingIgnoredDuringExecution enforces the desired behavior.
Detailed technical explanation
How to think about this question
PodAffinity uses the same topologyKey mechanism as podAntiAffinity, but with opposite semantics: it requires Pods to be placed on nodes that share a topology domain (e.g., kubernetes.io/hostname) with existing Pods matching the label selector. Under the hood, the scheduler evaluates the requiredDuringScheduling rule as a hard constraint during Pod placement; if no node can satisfy the co-location requirement, the Pod remains unscheduled. In real-world scenarios, this is critical for applications like distributed caches or machine learning training jobs that benefit from node-local communication to avoid network latency.
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 CKA 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 CKA question in full detail.
Workloads & Scheduling — This question tests Workloads & Scheduling — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Replace podAntiAffinity with podAffinity using requiredDuringSchedulingIgnoredDuringExecution for the app label. — Option A is correct because podAffinity with requiredDuringSchedulingIgnoredDuringExecution forces the scheduler to co-locate all Pods with the same app label on the same node. This directly overrides the default anti-affinity behavior that spreads Pods across nodes, ensuring low-latency inter-Pod communication by placing all replicas on a single node if possible.
What should I do if I get this CKA 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 CKA 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 CKA 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.