Question 910 of 1,616
Development with AWS ServiceshardMultiple ChoiceObjective-mapped

Preventing Data Loss in Lambda with SQS Dead-Letter Queue

This DVA-C02 practice question tests your understanding of development with aws services. 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 company runs a critical application on AWS Lambda that processes real-time financial transactions. The Lambda function is triggered by an SQS queue that receives messages from an API Gateway. Recently, the team has observed an increase in processing errors and occasional data loss. Upon investigation, they find that the Lambda function's concurrency limit is set to 5, and the SQS queue has a visibility timeout of 30 seconds. The function typically takes 2 seconds to process a message, but during peak hours, the queue depth grows to thousands of messages. The errors occur when the Lambda function throws an exception, causing the message to return to the queue after the visibility timeout expires. However, some messages are never processed again and are eventually lost. The team suspects that the messages are being sent to the dead-letter queue (DLQ) after multiple retries, but the DLQ is not configured. The team needs to ensure that no messages are lost and that processing errors are handled appropriately. What should the team do to resolve this issue?

Clue words in this question

Noticing these words before you look at the options changes how you read each choice.

  • Clue: "never"

    Why it matters: Absolute qualifier. True only if the statement has zero exceptions — be cautious of options that seem obvious but break down in edge cases.

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

Configure a dead-letter queue on the SQS source queue and set the maximum receives to 3. Implement error handling in the Lambda function to catch exceptions and log them.

Option D is correct because configuring a dead-letter queue on the SQS source queue ensures that messages that cannot be processed after the maximum receives are moved to the DLQ for later analysis and reprocessing, preventing data loss. The maximum receives should be set to a small number (e.g., 3) to avoid excessive retries. Additionally, implementing error handling in the Lambda function to catch exceptions and log them helps identify and fix processing issues. Option A is incorrect because increasing concurrency and visibility timeout does not prevent message loss after retries are exhausted without a DLQ. Option B is incorrect because CloudWatch alarms and on-failure destinations are for asynchronous Lambda invocations, not for SQS-triggered Lambda which uses event source mapping. Option C is incorrect because changing to synchronous invocation does not address the retry and loss problem and may cause API Gateway timeouts.

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.

  • Increase the Lambda concurrency limit to 100 and set the SQS visibility timeout to 60 seconds.

    Why it's wrong here

    While this may reduce backlog, it does not handle messages that fail repeatedly; without a DLQ, messages are still lost after retries.

  • Configure an Amazon CloudWatch alarm on the queue depth and set a Lambda function as the on-failure destination for asynchronous invocations.

    Why it's wrong here

    CloudWatch alarm does not prevent message loss; Lambda on-failure destination is not applicable to SQS-triggered functions.

  • Change the Lambda invocation mode to synchronous and use API Gateway as a proxy to invoke the function directly.

    Why it's wrong here

    Synchronous invocation does not solve the retry and loss issue; it may increase latency and complexity.

  • Configure a dead-letter queue on the SQS source queue and set the maximum receives to 3. Implement error handling in the Lambda function to catch exceptions and log them.

    Why this is correct

    A DLQ captures failed messages after retries, preventing data loss and allowing manual or automated reprocessing.

    Clue confirmation

    The clue word "never" in the question point toward this answer.

    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.

Visual reference

Client Recursive Resolver Root DNS (13 root servers) TLD DNS (.com, .org, …) Authoritative example.com query IP addr answer

Quick reference

Cloud Service Model Comparison

ModelYou ManageProvider ManagesExamples
IaaSOS, runtime, apps, dataHardware, hypervisor, networkingEC2, Azure VMs, GCP Compute Engine
PaaSApps and dataOS, runtime, middleware, hardwareElastic Beanstalk, Azure App Service
SaaSData and settings onlyEverything elseMicrosoft 365, Salesforce, Workday
FaaS / ServerlessFunction code onlyInfra, scaling, runtimeLambda, Azure Functions, Cloud Run
CaaSContainers and appsKubernetes, OS, hardwareEKS, AKS, GKE

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.

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.

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?

Development with AWS Services — This question tests Development with AWS Services — Read the scenario before looking for a memorised answer..

What is the correct answer to this question?

The correct answer is: Configure a dead-letter queue on the SQS source queue and set the maximum receives to 3. Implement error handling in the Lambda function to catch exceptions and log them. — Option D is correct because configuring a dead-letter queue on the SQS source queue ensures that messages that cannot be processed after the maximum receives are moved to the DLQ for later analysis and reprocessing, preventing data loss. The maximum receives should be set to a small number (e.g., 3) to avoid excessive retries. Additionally, implementing error handling in the Lambda function to catch exceptions and log them helps identify and fix processing issues. Option A is incorrect because increasing concurrency and visibility timeout does not prevent message loss after retries are exhausted without a DLQ. Option B is incorrect because CloudWatch alarms and on-failure destinations are for asynchronous Lambda invocations, not for SQS-triggered Lambda which uses event source mapping. Option C is incorrect because changing to synchronous invocation does not address the retry and loss problem and may cause API Gateway timeouts.

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.

Are there clue words in this question I should notice?

Yes — watch for: "never". Absolute qualifier. True only if the statement has zero exceptions — be cautious of options that seem obvious but break down in edge cases.

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 →

How Courseiva writes practice questions · Editorial policy

Keep practising

More DVA-C02 practice questions

Last reviewed: Jun 20, 2026

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.

Loading comments…

Sign in to join the discussion.

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.