- A
Configure a Lambda@Edge function to replace the 503 response.
Why wrong: Lambda@Edge works with CloudFront, not ALB.
- B
Enable the ALB's custom error response and specify the error page.
ALB supports custom error responses for 503 errors.
- C
Use Amazon CloudFront to cache a custom error page.
Why wrong: CloudFront can serve custom error pages but it's not an ALB feature.
- D
Use the ALB's fixed response action to return a custom error page.
Why wrong: Fixed response returns a static message, not a custom page from S3.
Question 318 of 1,750
Custom Error Responses for ALB with No Healthy Targets
This DOP-C02 practice question tests your understanding of resilient cloud solutions. 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.
A company uses AlB with target groups for a microservices architecture. They need to ensure that if a target group has no healthy targets, the ALB returns a custom error page instead of a 503. How can this be achieved?
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
✓
Enable the ALB's custom error response and specify the error page.
Option B is correct because ALB supports custom error responses, allowing you to specify a custom error page (e.g., an HTML file stored in Amazon S3) that is returned when a target group has no healthy targets. This feature directly replaces the default 503 status code with your custom content, without requiring additional services or compute resources.
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.
- ✗
Configure a Lambda@Edge function to replace the 503 response.
Why it's wrong here
Lambda@Edge works with CloudFront, not ALB.
- ✓
Enable the ALB's custom error response and specify the error page.
Why this is correct
ALB supports custom error responses for 503 errors.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
Use Amazon CloudFront to cache a custom error page.
Why it's wrong here
CloudFront can serve custom error pages but it's not an ALB feature.
- ✗
Use the ALB's fixed response action to return a custom error page.
Why it's wrong here
Fixed response returns a static message, not a custom page from S3.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates confuse the ALB's fixed response action (which is static and rule-based) with the custom error response feature (which is conditionally triggered by specific HTTP error codes like 503), leading them to incorrectly select option D.
Detailed technical explanation
How to think about this question
The ALB custom error response feature works by configuring a rule in the listener that matches the 503 status code and then specifying a custom response body (e.g., from an S3 bucket) or a redirect. Under the hood, the ALB evaluates target health via health checks and, if all targets are unhealthy, it generates a 503; the custom error response rule intercepts this at the listener level before the response is sent to the client. This is distinct from the fixed response action, which is static and not triggered by specific error codes.
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 media company stores terabytes of video archives that are accessed once a year for audit purposes. Moving these objects to a cold storage tier (Azure Archive, S3 Glacier, or Google Nearline) costs a fraction of hot storage. Questions like this test whether you understand storage tiers, access frequency tradeoffs, and retrieval latency requirements.
Quick reference
AWS S3 Storage Class Comparison
| Storage Class | Min Duration | Retrieval | Use Case |
|---|---|---|---|
| S3 Standard | None | Immediate | Frequently accessed data |
| S3 Standard-IA | 30 days | Immediate | Infrequent access, rapid retrieval |
| S3 One Zone-IA | 30 days | Immediate | Non-critical infrequent data |
| S3 Intelligent-Tiering | None | Immediate–hours | Unknown or changing access patterns |
| S3 Glacier Instant | 90 days | Milliseconds | Archive with instant retrieval |
| S3 Glacier Flexible | 90 days | Minutes–hours | Archive, flexible retrieval |
| S3 Glacier Deep Archive | 180 days | Hours | Long-term compliance archive |
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
- →
Resilient Cloud Solutions — study guide chapter
Learn the concepts, then practise the questions
- →
Resilient Cloud Solutions practice questions
Targeted practice on this topic area only
- →
All DOP-C02 questions
1,750 questions across all exam domains
- →
AWS Certified DevOps Engineer Professional DOP-C02 study guide
Full concept coverage aligned to exam objectives
- →
DOP-C02 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related DOP-C02 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Configuration Management and IaC practice questions
Practise DOP-C02 questions linked to Configuration Management and IaC.
Resilient Cloud Solutions practice questions
Practise DOP-C02 questions linked to Resilient Cloud Solutions.
Monitoring and Logging practice questions
Practise DOP-C02 questions linked to Monitoring and Logging.
Incident and Event Response practice questions
Practise DOP-C02 questions linked to Incident and Event Response.
Security and Compliance practice questions
Practise DOP-C02 questions linked to Security and Compliance.
SDLC Automation practice questions
Practise DOP-C02 questions linked to SDLC Automation.
DOP-C02 fundamentals practice questions
Practise DOP-C02 questions linked to DOP-C02 fundamentals.
DOP-C02 scenario practice questions
Practise DOP-C02 questions linked to DOP-C02 scenario.
DOP-C02 troubleshooting practice questions
Practise DOP-C02 questions linked to DOP-C02 troubleshooting.
Practice this exam
Start a free DOP-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 DOP-C02 question test?
Resilient Cloud Solutions — This question tests Resilient Cloud Solutions — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Enable the ALB's custom error response and specify the error page. — Option B is correct because ALB supports custom error responses, allowing you to specify a custom error page (e.g., an HTML file stored in Amazon S3) that is returned when a target group has no healthy targets. This feature directly replaces the default 503 status code with your custom content, without requiring additional services or compute resources.
What should I do if I get this DOP-C02 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 →
Keep practising
More DOP-C02 practice questions
- A company uses AWS CodePipeline with a multi-branch strategy. A new feature branch triggers a pipeline that runs unit te…
- A development team uses AWS CodeBuild to compile a Java application and run unit tests. The build takes 30 minutes, but…
- A company uses AWS CodePipeline with multiple stages: Source (Amazon S3), Build (AWS CodeBuild), and Deploy (AWS CodeDep…
- A company uses AWS CodeCommit for source control. Developers frequently push large binary files (e.g., compiled JARs) to…
- A company runs a Stateful application on EC2 that requires sticky sessions. They use an ALB with duration-based stickine…
- An organization uses AWS CodePipeline to orchestrate deployments to multiple environments (dev, test, prod). Each enviro…
Last reviewed: Jul 4, 2026
This DOP-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 DOP-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.