- A
Use a CloudFormation WaitCondition to pause stack creation until the DB instance is available.
Why wrong: WaitCondition pauses but does not prevent recreation; stack will still roll back and delete the DB instance if creation fails.
- B
Create the DB instance using a separate CloudFormation stack and reference it using Fn::ImportValue.
Why wrong: While this is a good practice, it does not directly address continuing from a failed state in the same stack.
- C
Apply a stack policy that prevents the DB instance from being deleted during stack updates.
Why wrong: Stack policy protects resources during updates, not during creation rollback.
- D
Use a CloudFormation custom resource to check for an existing DB instance and create it only if it does not exist.
Custom resource can implement logic to reuse an existing DB instance or create a new one, avoiding recreation on retry.
DVA-C02 Deployment Practice Question
This DVA-C02 practice question tests your understanding of deployment. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. 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.
A team uses AWS CloudFormation to manage infrastructure. They want to deploy a stack that includes an Amazon RDS DB instance. During deployment, the stack creation fails because the DB instance creation times out. The team wants to ensure that subsequent stack creation attempts do not recreate the DB instance from scratch but instead continue from the failed state. Which CloudFormation feature should they use?
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
Use a CloudFormation custom resource to check for an existing DB instance and create it only if it does not exist.
Option B is correct. CloudFormation stack creation rollback triggers with '--on-failure DO_NOTHING' or '--disable-rollback' will leave the failed resources in place so they can be resumed? Actually, CloudFormation does not support resuming a failed stack creation; it will roll back and delete resources. To avoid this, you can use a custom resource to check if the DB instance already exists, but the question asks for a feature to continue from failed state. The best approach is to use a custom resource or separate stack for the DB instance. Among options, only 'Custom resource' (Option A) can handle such logic, but the correct answer is B: Use a custom resource to check for existing DB instance and skip creation if it exists. However, Option A is also custom resource. Let's re-evaluate: The feature that allows you to conditionally create resources based on existing resources is 'Conditions' but that requires knowing the DB instance ID. 'Custom resource' can query existing DB and return a value to use in conditions. So Option B is correct. Option A (WaitCondition) is for signaling completion, not for conditional creation. Option C (Stack policy) protects resources but does not help with continuation. Option D (Change sets) are for updates, not creation rollback.
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.
- ✗
Use a CloudFormation WaitCondition to pause stack creation until the DB instance is available.
Why it's wrong here
WaitCondition pauses but does not prevent recreation; stack will still roll back and delete the DB instance if creation fails.
- ✗
Create the DB instance using a separate CloudFormation stack and reference it using Fn::ImportValue.
Why it's wrong here
While this is a good practice, it does not directly address continuing from a failed state in the same stack.
- ✗
Apply a stack policy that prevents the DB instance from being deleted during stack updates.
Why it's wrong here
Stack policy protects resources during updates, not during creation rollback.
- ✓
Use a CloudFormation custom resource to check for an existing DB instance and create it only if it does not exist.
Why this is correct
Custom resource can implement logic to reuse an existing DB instance or create a new one, avoiding recreation on retry.
Related concept
Read the scenario before looking for a memorised answer.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Many certification questions include familiar terms but test a specific constraint. Read the exact wording before choosing an answer that is generally true but wrong for this case.
Detailed technical explanation
How to think about this question
This question should be treated as a scenario, not a definition check. Identify the problem, the constraint and the best action. Then compare each option against those facts.
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.
- Use explanations to understand the rule behind the answer.
TExam Day Tips
- Underline the problem statement mentally.
- 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 cloud solutions architect for a retail company is evaluating services for a new workload. The correct answer here reflects best practice for the specific scenario described — not a general cloud recommendation. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Cloud exam questions reward reading the constraint carefully: the same technology can be right or wrong depending on the use case.
What to study next
Got this wrong? Here's your next step.
Identify which DVA-C02 exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
- →
Deployment — study guide chapter
Learn the concepts, then practise the questions
- →
Deployment practice questions
Targeted practice on this topic area only
- →
All DVA-C02 questions
1,616 questions across all exam domains
- →
AWS Certified Developer Associate DVA-C02 study guide
Full concept coverage aligned to exam objectives
- →
DVA-C02 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related DVA-C02 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Development with AWS Services practice questions
Practise DVA-C02 questions linked to Development with AWS Services.
Security practice questions
Practise DVA-C02 questions linked to Security.
Deployment practice questions
Practise DVA-C02 questions linked to Deployment.
Troubleshooting and Optimization practice questions
Practise DVA-C02 questions linked to Troubleshooting and Optimization.
DVA-C02 fundamentals practice questions
Practise DVA-C02 questions linked to DVA-C02 fundamentals.
DVA-C02 scenario practice questions
Practise DVA-C02 questions linked to DVA-C02 scenario.
DVA-C02 troubleshooting practice questions
Practise DVA-C02 questions linked to DVA-C02 troubleshooting.
Practice this exam
Start a free DVA-C02 practice session
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Questions learners often ask
What does this DVA-C02 question test?
Deployment — This question tests Deployment — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Use a CloudFormation custom resource to check for an existing DB instance and create it only if it does not exist. — Option B is correct. CloudFormation stack creation rollback triggers with '--on-failure DO_NOTHING' or '--disable-rollback' will leave the failed resources in place so they can be resumed? Actually, CloudFormation does not support resuming a failed stack creation; it will roll back and delete resources. To avoid this, you can use a custom resource to check if the DB instance already exists, but the question asks for a feature to continue from failed state. The best approach is to use a custom resource or separate stack for the DB instance. Among options, only 'Custom resource' (Option A) can handle such logic, but the correct answer is B: Use a custom resource to check for existing DB instance and skip creation if it exists. However, Option A is also custom resource. Let's re-evaluate: The feature that allows you to conditionally create resources based on existing resources is 'Conditions' but that requires knowing the DB instance ID. 'Custom resource' can query existing DB and return a value to use in conditions. So Option B is correct. Option A (WaitCondition) is for signaling completion, not for conditional creation. Option C (Stack policy) protects resources but does not help with continuation. Option D (Change sets) are for updates, not creation rollback.
What should I do if I get this DVA-C02 question wrong?
Identify which DVA-C02 exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
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 →
Last reviewed: Jun 20, 2026
This DVA-C02 practice question is part of Courseiva's free Amazon Web Services 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 DVA-C02 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.