- A
Configure the Auto Scaling group to span multiple AZs and enable health checks to replace unhealthy instances.
Multiple AZs provide high availability and health checks ensure quick replacement.
- B
Use a larger AMI to reduce boot times.
Why wrong: Boot time reduction does not solve the AZ failure issue.
- C
Increase the instance size of the EC2 instances to handle more traffic.
Why wrong: Instance size impacts performance, not resilience to AZ failure.
- D
Configure the Auto Scaling group to launch instances in a single AZ with a larger instance count.
Why wrong: A single AZ is a single point of failure.
Question 1,252 of 1,750
DOP-C02 Resilient Cloud Solutions Practice Question
This DOP-C02 practice question tests your understanding of resilient cloud solutions. 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 web application on EC2 instances behind an Application Load Balancer (ALB) across multiple Availability Zones. During a recent failure of one AZ, the application experienced downtime because the Auto Scaling group did not launch new instances quickly enough. What should a DevOps engineer do to improve resilience?
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 the Auto Scaling group to span multiple AZs and enable health checks to replace unhealthy instances.
Option A is correct because configuring the Auto Scaling group to span multiple Availability Zones (AZs) and enabling health checks ensures that if an entire AZ fails, the Auto Scaling group can launch replacement instances in the remaining healthy AZs. The ALB health checks detect unhealthy instances and trigger the Auto Scaling group to replace them, reducing downtime. This approach leverages the fault isolation of multiple AZs and the automatic scaling capabilities of AWS Auto Scaling.
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 the Auto Scaling group to span multiple AZs and enable health checks to replace unhealthy instances.
Why this is correct
Multiple AZs provide high availability and health checks ensure quick replacement.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
Use a larger AMI to reduce boot times.
Why it's wrong here
Boot time reduction does not solve the AZ failure issue.
- ✗
Increase the instance size of the EC2 instances to handle more traffic.
Why it's wrong here
Instance size impacts performance, not resilience to AZ failure.
- ✗
Configure the Auto Scaling group to launch instances in a single AZ with a larger instance count.
Why it's wrong here
A single AZ is a single point of failure.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often focus on instance-level improvements (like larger AMIs or instance sizes) instead of architectural resilience across Availability Zones, which is the core requirement for AZ failure scenarios.
Detailed technical explanation
How to think about this question
Under the hood, the Auto Scaling group uses the EC2 health check (status checks) and ELB health checks to determine instance health. When an AZ fails, the Auto Scaling group's rebalancing process distributes new instances across the remaining AZs based on the group's subnets. The ALB's health check interval (default 30 seconds) and unhealthy threshold (default 2) determine how quickly an instance is marked unhealthy, and the Auto Scaling group's cooldown period (default 300 seconds) can delay new launches if not tuned. In a real-world scenario, setting a lower health check interval and using a warm-up period for the target group can further reduce recovery time.
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
An e-commerce site experiences heavy traffic on Black Friday and near-zero traffic during off-peak weeks. Rather than provisioning permanent large VMs, the team uses auto-scaling groups that add capacity automatically under load and reduce it overnight. Questions like this test whether you understand elasticity, availability zones, and cloud compute scaling patterns.
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: Configure the Auto Scaling group to span multiple AZs and enable health checks to replace unhealthy instances. — Option A is correct because configuring the Auto Scaling group to span multiple Availability Zones (AZs) and enabling health checks ensures that if an entire AZ fails, the Auto Scaling group can launch replacement instances in the remaining healthy AZs. The ALB health checks detect unhealthy instances and trigger the Auto Scaling group to replace them, reducing downtime. This approach leverages the fault isolation of multiple AZs and the automatic scaling capabilities of AWS Auto Scaling.
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.