← SOA-C02·Amazon Web Services

Question 145 of 1,546

Reliability and Business Continuity →easyMultiple SelectObjective-mapped

EC2 High Availability with Multi-AZ and Auto Scaling

This SOA-C02 practice question tests your understanding of reliability and business continuity. 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.

Which TWO actions should a SysOps administrator take to ensure high availability of a web application running on EC2 instances? (Choose two.)

A
Enable termination protection on all EC2 instances.
Why wrong: Termination protection prevents manual deletion but does not replace unhealthy instances.
B
Launch all EC2 instances in a single Availability Zone.
Why wrong: Single AZ is a single point of failure.
C
Use a larger instance type for all EC2 instances.
Why wrong: Instance size does not affect availability.
D
Configure an Auto Scaling group with a health check to replace unhealthy instances.
Auto Scaling automatically replaces unhealthy instances.
E
Deploy EC2 instances across multiple Availability Zones.
Distributing instances across AZs provides fault isolation.

Full breakdown with real-world context →

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 an Auto Scaling group with a health check to replace unhealthy instances.

Option D is correct because an Auto Scaling group with a health check can automatically detect and replace unhealthy EC2 instances, ensuring that the web application remains available even if an instance fails. The health check can be configured to use Elastic Load Balancing (ELB) health checks or EC2 status checks to determine instance health, and the Auto Scaling group will launch a new instance to replace any that fails the health check.

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.

✗
Enable termination protection on all EC2 instances.
Why it's wrong here
Termination protection prevents manual deletion but does not replace unhealthy instances.
✗
Launch all EC2 instances in a single Availability Zone.
Why it's wrong here
Single AZ is a single point of failure.
✗
Use a larger instance type for all EC2 instances.
Why it's wrong here
Instance size does not affect availability.
✓
Configure an Auto Scaling group with a health check to replace unhealthy instances.
Why this is correct
Auto Scaling automatically replaces unhealthy instances.
Related concept
Read the scenario before looking for a memorised answer.
✓
Deploy EC2 instances across multiple Availability Zones.
Why this is correct
Distributing instances across AZs provides fault isolation.
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 often confuse termination protection (a safety feature) with high availability, or think that larger instance types inherently provide fault tolerance, when in fact only redundancy across multiple Availability Zones and automated health-based replacement ensure high availability.

Detailed technical explanation

How to think about this question

Auto Scaling groups use the EC2 Auto Scaling service to maintain a desired number of instances, and when combined with Elastic Load Balancing, they can distribute traffic across healthy instances in multiple Availability Zones. The health check grace period (default 300 seconds) allows instances time to boot before health checks begin, preventing premature replacement. In a real-world scenario, if an instance fails due to a hardware issue, the Auto Scaling group will terminate it and launch a new one in a different AZ, ensuring the application remains available without manual intervention.

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.

Related SOA-C02 practice-question pages

Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.

Monitoring, Logging, and Remediation practice questions

Practise SOA-C02 questions linked to Monitoring, Logging, and Remediation.

Reliability and Business Continuity practice questions

Practise SOA-C02 questions linked to Reliability and Business Continuity.

Deployment, Provisioning, and Automation practice questions

Practise SOA-C02 questions linked to Deployment, Provisioning, and Automation.

Security and Compliance practice questions

Practise SOA-C02 questions linked to Security and Compliance.

Networking and Content Delivery practice questions

Practise SOA-C02 questions linked to Networking and Content Delivery.

Cost and Performance Optimization practice questions

Practise SOA-C02 questions linked to Cost and Performance Optimization.

SOA-C02 fundamentals practice questions

Practise SOA-C02 questions linked to SOA-C02 fundamentals.

SOA-C02 scenario practice questions

Practise SOA-C02 questions linked to SOA-C02 scenario.

SOA-C02 troubleshooting practice questions

Practise SOA-C02 questions linked to SOA-C02 troubleshooting.

Practice this exam

Start a free SOA-C02 practice session

Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.

10 questions 20 questions 30 questions 50 questions Timed 30

SOA-C02 practice-test guide →Study guide →Browse all practice tests

FAQ

Questions learners often ask

What does this SOA-C02 question test?

Reliability and Business Continuity — This question tests Reliability and Business Continuity — Read the scenario before looking for a memorised answer..

What is the correct answer to this question?

The correct answer is: Configure an Auto Scaling group with a health check to replace unhealthy instances. — Option D is correct because an Auto Scaling group with a health check can automatically detect and replace unhealthy EC2 instances, ensuring that the web application remains available even if an instance fails. The health check can be configured to use Elastic Load Balancing (ELB) health checks or EC2 status checks to determine instance health, and the Auto Scaling group will launch a new instance to replace any that fails the health check.

What should I do if I get this SOA-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 →

How Courseiva writes practice questions · Editorial policy

Same concept, more angles

1 more ways this is tested on SOA-C02

These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.

Variation 1. Which TWO actions improve the availability of an application running on EC2 instances in a single Auto Scaling group? (Choose 2)

medium

✓ A.Use an Elastic Load Balancer with health checks to route traffic only to healthy instances.
B.Increase the instance size to handle higher load.
C.Create a CloudWatch alarm to notify when the CPU utilization exceeds 80%.
D.Enable EBS optimization on the instances.
✓ E.Configure the Auto Scaling group to launch instances in multiple Availability Zones.

Why A: Option A is correct because an Elastic Load Balancer (ELB) performs health checks against EC2 instances and automatically routes traffic only to instances that pass those checks. If an instance becomes unhealthy, the ELB stops sending traffic to it, preventing user requests from reaching a failing instance and thereby improving application availability.

Keep practising

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…

This SOA-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 SOA-C02 exam.