- A
Rebuild the environment with a larger instance type to handle the load.
Why wrong: Instance size is not relevant; the issue is port mismatch.
- B
Use the Elastic Beanstalk console to update the environment's software configuration.
Why wrong: Software configuration does not directly fix the port issue; it's an application-level configuration.
- C
Review the application logs in CloudWatch Logs for error messages.
Why wrong: Logs may show errors but not the port; the nginx config is more direct.
- D
Check the application's listening port by viewing the nginx configuration files in the platform hooks and ensure the app listens on the expected port (e.g., 8080).
Elastic Beanstalk's nginx proxy forwards requests to the application on a specific port (usually 8080). If the app listens on a different port, it causes 502 errors.
DOP-C02 SDLC Automation Practice Question
This DOP-C02 practice question tests your understanding of sdlc automation. 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.
An organization uses AWS Elastic Beanstalk to deploy a web application. The deployment fails with a '502 Bad Gateway' error after the environment update. The health status shows 'Severe'. Investigation reveals that the application is not binding to the port that the nginx proxy expects. What is the most efficient way to diagnose and resolve this issue?
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
Check the application's listening port by viewing the nginx configuration files in the platform hooks and ensure the app listens on the expected port (e.g., 8080).
The 502 Bad Gateway error in Elastic Beanstalk typically occurs when the nginx reverse proxy cannot forward requests to the application because the application is not listening on the expected port (default 8080). Checking the nginx configuration files in the platform hooks and verifying the application's listening port directly addresses the root cause, as the proxy expects the app to bind to a specific port. This is the most efficient diagnostic step because it targets the exact mismatch between the proxy and the application.
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.
- ✗
Rebuild the environment with a larger instance type to handle the load.
Why it's wrong here
Instance size is not relevant; the issue is port mismatch.
- ✗
Use the Elastic Beanstalk console to update the environment's software configuration.
Why it's wrong here
Software configuration does not directly fix the port issue; it's an application-level configuration.
- ✗
Review the application logs in CloudWatch Logs for error messages.
Why it's wrong here
Logs may show errors but not the port; the nginx config is more direct.
- ✓
Check the application's listening port by viewing the nginx configuration files in the platform hooks and ensure the app listens on the expected port (e.g., 8080).
Why this is correct
Elastic Beanstalk's nginx proxy forwards requests to the application on a specific port (usually 8080). If the app listens on a different port, it causes 502 errors.
Related concept
Read the scenario before looking for a memorised answer.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates assume a 502 error always indicates an application crash or resource exhaustion, leading them to check logs or scale up, rather than recognizing it as a proxy-to-application port mismatch that is best diagnosed by examining the nginx configuration and application binding.
Trap categories for this question
Command / output trap
Logs may show errors but not the port; the nginx config is more direct.
Detailed technical explanation
How to think about this question
Elastic Beanstalk's nginx proxy is configured via platform hooks (e.g., .platform/nginx/conf.d/) to forward requests to a local port (default 8080). The application must bind to 0.0.0.0:8080; if it binds to a different port (e.g., 3000) or only to localhost, nginx returns 502. The health check endpoint (e.g., /health) also fails, causing 'Severe' status. A common real-world scenario is a developer hardcoding a port in the app code (e.g., process.env.PORT || 3000) without aligning with EB's expected port.
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 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
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.
- →
SDLC Automation — study guide chapter
Learn the concepts, then practise the questions
- →
SDLC Automation 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?
SDLC Automation — This question tests SDLC Automation — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Check the application's listening port by viewing the nginx configuration files in the platform hooks and ensure the app listens on the expected port (e.g., 8080). — The 502 Bad Gateway error in Elastic Beanstalk typically occurs when the nginx reverse proxy cannot forward requests to the application because the application is not listening on the expected port (default 8080). Checking the nginx configuration files in the platform hooks and verifying the application's listening port directly addresses the root cause, as the proxy expects the app to bind to a specific port. This is the most efficient diagnostic step because it targets the exact mismatch between the proxy and the application.
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.