AWS Cloud Practitioner Reliability &
Fault-Tolerant Architecture Practice
Test 2026–2027 | Resilience Questions,
Answers & Detailed Rationales
1. A company runs a critical application on a single Amazon EC2 instance. The
company wants to improve reliability with minimal architectural changes.
Which solution is MOST appropriate?
A. Increase the EC2 instance size
B. Deploy the application across multiple Availability Zones
C. Move the application to an Amazon S3 bucket
D. Disable automatic software updates
Answer: B. Deploy the application across multiple Availability Zones
Rationale: Distributing application resources across multiple Availability Zones
reduces the impact of an Availability Zone failure and improves fault tolerance.
, 2. Which AWS capability BEST supports the reliability principle of
automatically replacing unhealthy compute resources?
A. Amazon CloudWatch alarms combined with Amazon EC2 Auto Scaling
B. AWS Artifact
C. AWS Billing Conductor
D. Amazon Macie
Answer: A. Amazon CloudWatch alarms combined with Amazon EC2 Auto
Scaling
Rationale: CloudWatch can monitor resource health and trigger scaling actions,
while EC2 Auto Scaling can replace unhealthy instances automatically.
3. An application must continue operating if one Availability Zone becomes
unavailable. Which architecture BEST meets this requirement?
A. One EC2 instance in one Availability Zone
B. Multiple EC2 instances distributed across Availability Zones
C. Multiple EBS volumes in one Availability Zone
D. One larger EC2 instance with provisioned IOPS
Answer: B. Multiple EC2 instances distributed across Availability Zones
Rationale: Multi-AZ deployment removes dependence on a single Availability
Zone and is a fundamental AWS high-availability pattern.
4. What is the PRIMARY purpose of fault-tolerant architecture?
A. Eliminate all operating costs
B. Ensure the system can continue operating despite component failures
C. Prevent every possible security incident
D. Maximize the number of AWS services used
,Answer: B. Ensure the system can continue operating despite component
failures
Rationale: Fault tolerance means a system can continue providing service even
when individual components fail.
5. A company wants EC2 instances to be distributed evenly across multiple
Availability Zones. Which AWS service is MOST appropriate?
A. Amazon EC2 Auto Scaling
B. AWS Artifact
C. Amazon Inspector
D. AWS Budgets
Answer: A. Amazon EC2 Auto Scaling
Rationale: EC2 Auto Scaling supports distributing instances across Availability
Zones and maintaining the desired capacity when failures occur.
6. Which statement BEST describes an Availability Zone?
A. A geographic continent
B. One or more discrete data centers with redundant power and networking
within an AWS Region
C. A global AWS edge cache
D. A customer's private data center
Answer: B. One or more discrete data centers with redundant power and
networking within an AWS Region
Rationale: Availability Zones are isolated locations within an AWS Region
designed to provide fault isolation and high availability.
, 7. A workload requires protection against an entire AWS Region becoming
unavailable. Which approach provides the strongest architectural
improvement?
A. Deploy resources in multiple Availability Zones within one Region only
B. Deploy the workload across multiple AWS Regions
C. Use a larger EC2 instance
D. Add additional EBS volumes
Answer: B. Deploy the workload across multiple AWS Regions
Rationale: Multi-Region architecture can protect against Region-level
disruptions, whereas Multi-AZ primarily protects against failures within a
Region.
8. Which AWS service can automatically route users to a healthy endpoint
when an endpoint becomes unavailable?
A. Amazon Route 53
B. AWS Artifact
C. Amazon GuardDuty
D. AWS Config
Answer: A. Amazon Route 53
Rationale: Route 53 health checks and routing policies can direct traffic away
from unhealthy endpoints.
9. A company wants to distribute incoming application traffic among multiple
EC2 instances. Which service should it use?
A. Elastic Load Balancing
B. Amazon S3 Glacier
Fault-Tolerant Architecture Practice
Test 2026–2027 | Resilience Questions,
Answers & Detailed Rationales
1. A company runs a critical application on a single Amazon EC2 instance. The
company wants to improve reliability with minimal architectural changes.
Which solution is MOST appropriate?
A. Increase the EC2 instance size
B. Deploy the application across multiple Availability Zones
C. Move the application to an Amazon S3 bucket
D. Disable automatic software updates
Answer: B. Deploy the application across multiple Availability Zones
Rationale: Distributing application resources across multiple Availability Zones
reduces the impact of an Availability Zone failure and improves fault tolerance.
, 2. Which AWS capability BEST supports the reliability principle of
automatically replacing unhealthy compute resources?
A. Amazon CloudWatch alarms combined with Amazon EC2 Auto Scaling
B. AWS Artifact
C. AWS Billing Conductor
D. Amazon Macie
Answer: A. Amazon CloudWatch alarms combined with Amazon EC2 Auto
Scaling
Rationale: CloudWatch can monitor resource health and trigger scaling actions,
while EC2 Auto Scaling can replace unhealthy instances automatically.
3. An application must continue operating if one Availability Zone becomes
unavailable. Which architecture BEST meets this requirement?
A. One EC2 instance in one Availability Zone
B. Multiple EC2 instances distributed across Availability Zones
C. Multiple EBS volumes in one Availability Zone
D. One larger EC2 instance with provisioned IOPS
Answer: B. Multiple EC2 instances distributed across Availability Zones
Rationale: Multi-AZ deployment removes dependence on a single Availability
Zone and is a fundamental AWS high-availability pattern.
4. What is the PRIMARY purpose of fault-tolerant architecture?
A. Eliminate all operating costs
B. Ensure the system can continue operating despite component failures
C. Prevent every possible security incident
D. Maximize the number of AWS services used
,Answer: B. Ensure the system can continue operating despite component
failures
Rationale: Fault tolerance means a system can continue providing service even
when individual components fail.
5. A company wants EC2 instances to be distributed evenly across multiple
Availability Zones. Which AWS service is MOST appropriate?
A. Amazon EC2 Auto Scaling
B. AWS Artifact
C. Amazon Inspector
D. AWS Budgets
Answer: A. Amazon EC2 Auto Scaling
Rationale: EC2 Auto Scaling supports distributing instances across Availability
Zones and maintaining the desired capacity when failures occur.
6. Which statement BEST describes an Availability Zone?
A. A geographic continent
B. One or more discrete data centers with redundant power and networking
within an AWS Region
C. A global AWS edge cache
D. A customer's private data center
Answer: B. One or more discrete data centers with redundant power and
networking within an AWS Region
Rationale: Availability Zones are isolated locations within an AWS Region
designed to provide fault isolation and high availability.
, 7. A workload requires protection against an entire AWS Region becoming
unavailable. Which approach provides the strongest architectural
improvement?
A. Deploy resources in multiple Availability Zones within one Region only
B. Deploy the workload across multiple AWS Regions
C. Use a larger EC2 instance
D. Add additional EBS volumes
Answer: B. Deploy the workload across multiple AWS Regions
Rationale: Multi-Region architecture can protect against Region-level
disruptions, whereas Multi-AZ primarily protects against failures within a
Region.
8. Which AWS service can automatically route users to a healthy endpoint
when an endpoint becomes unavailable?
A. Amazon Route 53
B. AWS Artifact
C. Amazon GuardDuty
D. AWS Config
Answer: A. Amazon Route 53
Rationale: Route 53 health checks and routing policies can direct traffic away
from unhealthy endpoints.
9. A company wants to distribute incoming application traffic among multiple
EC2 instances. Which service should it use?
A. Elastic Load Balancing
B. Amazon S3 Glacier
