CKA Workloads and Scheduling Practice Question
A StatefulSet named 'db' manages 3 pods. The pods are named db-0, db-1, db-2. What is the expected behavior when the StatefulSet's pod management policy is set to OrderedReady and you scale down from 3 to 1 replica?
⚠ Common exam trap
Kubernetes often tests the misconception that scaling down deletes pods in ascending order (starting from db-0) or that all pods are deleted at once, but the correct behavior for OrderedReady is reverse ordinal deletion.
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
✓
Pod db-2 is deleted, then db-1, and db-0 remains.
With the OrderedReady pod management policy, scaling down a StatefulSet deletes pods in reverse ordinal order, starting from the highest index. When scaling from 3 to 1 replica, pods db-2 (index 2) is deleted first, then db-1 (index 1), leaving db-0 (index 0) running. This ensures that each pod is fully terminated before the next one is deleted, maintaining the ordered startup and shutdown guarantees.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
All pods are deleted simultaneously.
Why it's wrong here
Scaling down a StatefulSet with the default podManagementPolicy of OrderedReady never deletes pods in parallel. The StatefulSet controller removes pods one at a time, starting from the highest ordinal, and waits for the previous pod to be fully terminated before proceeding. Therefore, deleting all three pods simultaneously violates the ordered, sequential scale-down guarantee of StatefulSets.
- ✓
Pod db-2 is deleted, then db-1, and db-0 remains.
Why this is correct
When you scale a StatefulSet from 3 replicas to 1 with the default OrderedReady policy, the controller deletes pods in reverse ordinal order: db-2 is terminated first, then db-1, and the process stops once only the pod with ordinal 0 remains. This maintains the StatefulSet identity and ordering guarantees, ensuring db-0 is the final surviving member. Each deletion is completed before the next pod is terminated, so db-0 is never at risk of being deleted.
- ✗
Only pod db-2 is deleted; db-1 and db-0 remain.
Why it's wrong here
Scaling from 3 replicas to 1 removes every pod whose ordinal is greater than or equal to the desired replica count; that includes both db-2 and db-1, not just db-2. The StatefulSet controller keeps terminating pods in reverse order until the number of running pods equals replicas, so db-0 remains only because its ordinal 0 is less than the desired count of 1. Stopping after db-2 would leave two pods, which does not match the requested scale.
- ✗
Pod db-0 is deleted first, then db-1, and db-2 remains.
Why it's wrong here
StatefulSet scale-down does not proceed forward from the lowest ordinal; it always terminates the highest ordinal first to preserve the original creation and startup ordering. Selecting db-0 first would reverse the ordinal lifecycle and break the stable pod identity guarantees that StatefulSets provide. With OrderedReady, db-0 is the last pod to be removed during scale-down, not the first, and in a scale to 1 it is never deleted at all.
About these practice questions
One of 726 original CKA 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 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.