Quick Answer
The answer is the health check path, interval, and threshold. These three configurations directly control how the Application Load Balancer determines instance health: the path defines which endpoint is probed, the interval sets how often probes are sent, and the threshold dictates how many consecutive failures mark an instance unhealthy. Misconfiguring any of these—such as a path returning a non-2xx/3xx status, an interval too short causing probe congestion, or a threshold too low triggering flapping—can cause healthy instances to be erroneously deregistered, producing those intermittent 503 errors. On the AWS Certified DevOps Engineer Professional DOP-C02 exam, this scenario tests your understanding of health check mechanics versus unrelated features like cross-zone load balancing or stickiness, which are common distractors. Remember the trap: always isolate health check tuning from traffic distribution settings. A useful memory tip is “PATH, PACE, PATIENCE”—verify the path, pace the interval, and set a patient threshold to avoid false negatives.
This DOP-C02 practice question tests your understanding of incident and event response. This is a configuration task: choose the command set that satisfies every stated requirement. Small differences — like 'secret' vs 'password' or 'transport input ssh' vs 'all' — change whether the answer is correct. 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 web application on EC2 instances behind an Application Load Balancer. The application is experiencing intermittent 503 errors. The DevOps team suspects that the target group's health check settings may be causing healthy instances to be marked as unhealthy. Which THREE configurations should the team review?
Stickiness setting
Why wrong: Stickiness does not affect health checks.
Health check interval
Too short an interval may cause false negatives.
Healthy threshold count
A low threshold may mark instances unhealthy prematurely.
Health check path
A wrong path can cause false unhealthy status.
Cross-zone load balancing setting
Why wrong: This affects traffic distribution, not health.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
Health check interval
Options A, C, and E are correct. Health check path, interval, and threshold all affect how the ALB determines instance health. Option B is wrong because cross-zone load balancing does not affect health checks; D is wrong because stickiness is about session persistence.
Key principle: NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.
Answer analysis
For each option: why learners choose it and why it is or isn't the right answer here.
Stickiness setting
Why it's wrong here
Stickiness does not affect health checks.
Health check interval
Why this is correct
Too short an interval may cause false negatives.
Related concept
Static NAT maps one inside address to one outside address.
Healthy threshold count
Why this is correct
A low threshold may mark instances unhealthy prematurely.
Related concept
Static NAT maps one inside address to one outside address.
Health check path
Why this is correct
A wrong path can cause false unhealthy status.
Related concept
Static NAT maps one inside address to one outside address.
Cross-zone load balancing setting
Why it's wrong here
This affects traffic distribution, not health.
Common exam traps
NAT is not only about the public address. The inside/outside interface roles and the ACL or rule that matches traffic are just as important.
Detailed technical explanation
NAT questions usually test address translation, overload/PAT behaviour, static mappings and whether the right traffic is being translated. Read the interface direction and address terms carefully.
Key takeaway
NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.
Real-world example
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. NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated. 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
Review the four NAT address types (inside local, inside global, outside local, outside global), PAT port overload, and static vs dynamic NAT use cases. Then practise related DOP-C02 NAT questions on configuration and troubleshooting.
Incident and Event Response — study guide chapter
Learn the concepts, then practise the questions
Incident and Event Response practice questions
Targeted practice on this topic area only
All DOP-C02 questions
1,740 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
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Practise DOP-C02 questions linked to Configuration Management and IaC.
Practise DOP-C02 questions linked to Resilient Cloud Solutions.
Practise DOP-C02 questions linked to Monitoring and Logging.
Practise DOP-C02 questions linked to Incident and Event Response.
Practise DOP-C02 questions linked to Security and Compliance.
Practise DOP-C02 questions linked to SDLC Automation.
Practise DOP-C02 questions linked to DOP-C02 fundamentals.
Practise DOP-C02 questions linked to DOP-C02 scenario.
Practise DOP-C02 questions linked to DOP-C02 troubleshooting.
Practice this exam
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Incident and Event Response — This question tests Incident and Event Response — Static NAT maps one inside address to one outside address..
The correct answer is: Health check interval — Options A, C, and E are correct. Health check path, interval, and threshold all affect how the ALB determines instance health. Option B is wrong because cross-zone load balancing does not affect health checks; D is wrong because stickiness is about session persistence.
Review the four NAT address types (inside local, inside global, outside local, outside global), PAT port overload, and static vs dynamic NAT use cases. Then practise related DOP-C02 NAT questions on configuration and troubleshooting.
Static NAT maps one inside address to one outside address.
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
Last reviewed: Jun 20, 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.