SAA-C03 Practice Test 2 — 25 Questions

Question 1

Several EC2 instances in different Availability Zones need to read and write the same shared file system. The file storage should stay available if one AZ has a problem. Which service should the team choose?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Amazon EFS. Amazon EFS provides a fully managed, scalable, and elastic NFS file system that can be mounted concurrently by multiple EC2 instances across different Availability Zones. It is designed for high availability and durability by storing data redundantly across multiple AZs within a region, ensuring continued access even if one AZ fails.

Answer

Amazon EBS

Answer

Amazon S3 only

Answer

Instance store

Question 2

A team needs a relational database solution that can automatically fail over to a standby instance if the primary database becomes unavailable. They want the standby to be located in a different Availability Zone. Which RDS/Aurora configuration best satisfies this requirement?

Accepted Answer

Multi-AZ deployment with an automatically managed standby in a different Availability Zone and automatic failover.. A Multi-AZ RDS deployment automatically provisions and maintains a standby instance in a different Availability Zone, and the failover is handled automatically by AWS without manual intervention. This meets the requirement for automatic failover to a standby in a different AZ, which is the core purpose of Multi-AZ deployments.

Answer

Single-AZ DB deployment and rely on manual snapshot restore during failures.

Answer

Enable read replicas only, and promote a replica manually when the primary fails.

Answer

Enable point-in-time recovery (PITR) without configuring any Multi-AZ standby.

Question 3

Your web application runs on EC2 instances behind an Application Load Balancer (ALB). During traffic spikes, p95 response time increases, but average CPU utilization remains below 40%. The current Auto Scaling policy scales based on average CPU%. What should you change to improve performance during spikes?

Accepted Answer

Scale on a request-driven metric such as ALB RequestCount per target (or target-group request rate). The p95 response time is increasing during traffic spikes while CPU utilization remains low, indicating that the bottleneck is not compute capacity but rather request handling or connection overhead. By scaling on ALB RequestCountPerTarget, you directly target the metric causing latency—each target's request load—rather than an indirect metric like CPU. This ensures that new instances are launched precisely when individual targets are overwhelmed by requests, reducing queueing delays and improving response times.

Answer

Keep scaling on CPU% to avoid over-scaling

Answer

Disable scaling and manually increase capacity during business hours

Answer

Scale only when network packet drops fall below a threshold

Question 4

An event-driven order processing service consumes messages from an Amazon SQS Standard queue. After a deployment, about 1% of messages start failing validation because a required field is missing. The consumer catches the exception and returns control, so the messages are retried. However, those poison messages keep reappearing and repeatedly consuming processing time for hours, delaying handling of valid messages. What is the most resilient way to handle the poison messages while keeping the system available?

Accepted Answer

Configure an SQS redrive policy to send messages to a dead-letter queue (DLQ) after a limited number of receives (maxReceiveCount).. Configuring an SQS redrive policy with a maxReceiveCount (e.g., 3–5) automatically moves messages that repeatedly fail processing to a dead-letter queue (DLQ) after the specified number of receives. This isolates the poison messages, preventing them from consuming visibility timeout and processing resources, while allowing valid messages to be handled without delay. The DLQ can then be analyzed or reprocessed offline, maintaining system availability.

Answer

Set the consumer visibility timeout to a very large value so failing messages are hidden for hours.

Answer

Switch the SQS queue from Standard to FIFO so poison messages do not retry.

Answer

Increase the consumer concurrency indefinitely so the system processes all messages even if some fail validation.

Question 5

An Auto Scaling group behind an Application Load Balancer frequently replaces new EC2 instances. The application needs ~6 minutes to warm up after instance launch. However, the ALB target group health checks start immediately and mark the targets unhealthy until the application is ready. Because the targets become unhealthy early, the Auto Scaling group then terminates the instances and launches replacements, creating a repeated unhealthy/termination loop.

What configuration change will most directly improve recovery by preventing premature ASG termination while the application is warming up?

Accepted Answer

Set a health check grace period on the Auto Scaling group that exceeds the application startup/warm-up time.. The health check grace period on an Auto Scaling group (ASG) allows a newly launched EC2 instance to bypass health check failures for a specified duration. By setting this grace period to exceed the application's ~6-minute warm-up time, the ASG will not prematurely terminate the instance based on ALB health check results. This directly breaks the unhealthy/termination loop while the application initializes.

Answer

Increase the Auto Scaling group's desired capacity to a higher number than required.

Answer

Disable ALB target group health checks so instances are considered healthy as soon as they register.

Answer

Change the Auto Scaling health check type from ELB to EC2 so the ALB will no longer determine instance health.

Question 6

You use Amazon CloudFront in front of a private content S3 origin. To mitigate an OWASP Top 10 issue, you created a WAF web ACL and associated it to the CloudFront distribution, but attacks are still reaching the origin.

CloudWatch logs show the web ACL rules never match for the CloudFront requests.

What is the most likely configuration mistake?

Accepted Answer

The WAF web ACL intended for CloudFront must be created in the us-east-1 (N. Virginia) region (CloudFront scope), even if the rest of the stack is in another region.. When using AWS WAF with CloudFront, the web ACL must be created in the US East (N. Virginia) region (us-east-1) because CloudFront is a global service that only supports WAF web ACLs with a global scope, which are always defined in us-east-1. If the web ACL is created in any other region, it will be a regional web ACL and cannot be associated with a CloudFront distribution, causing the rules to never be evaluated against incoming requests. This explains why CloudWatch logs show no rule matches—the web ACL is effectively not attached to the CloudFront distribution.

Answer

WAF rules only evaluate requests after they reach the origin, so the absence of matches means the origin is blocking traffic first.

Answer

For CloudFront, you must use a regional WAF endpoint and cannot use a global web ACL.

Answer

WAF web ACL rules never apply to signed URLs or signed cookies, so the web ACL is bypassed by design.

Question 7

A claims portal stores audit logs in S3. The compliance team requires that logs cannot be overwritten or deleted for seven years. What should be configured?

Accepted Answer

S3 Object Lock in compliance mode with an appropriate retention period. C is correct because S3 Object Lock in compliance mode enforces a write-once-read-many (WORM) model that prevents any user, including the root user, from overwriting or deleting objects for the specified retention period. This meets the compliance team's requirement that logs cannot be altered or removed for seven years, as compliance mode provides the highest level of protection and cannot be bypassed or shortened.

Answer

S3 server access logging

Answer

S3 versioning only

Answer

S3 lifecycle expiration after seven years

Question 8

A retail analytics app uses Amazon RDS for PostgreSQL. Read traffic is growing, and the database CPU spikes mainly due to SELECT-heavy workloads. Writes are less frequent, and the app can tolerate eventually consistent reads for the reports. What is the most appropriate AWS-native way to improve read performance with minimal application changes?

Accepted Answer

Create an RDS read replica and point the reporting queries to the replica endpoint.. Creating an RDS read replica is the most appropriate AWS-native solution because it offloads SELECT-heavy workloads from the primary database instance to a read-only copy, reducing CPU spikes on the primary. The application can tolerate eventually consistent reads for reports, which is exactly the consistency model of RDS read replicas (typically sub-second replication lag). This requires minimal application changes—only updating the reporting queries to point to the replica endpoint—and fully leverages PostgreSQL's built-in replication capabilities.

Answer

Switch the cluster to DynamoDB without redesigning the data model.

Answer

Enable S3 event notifications to trigger a Lambda function after each write to the database.

Answer

Replace the RDS instance class with a smaller size to reduce cost and improve performance.

Question 9

A team accidentally updates critical rows in an Amazon RDS for PostgreSQL database. Automated backups are enabled. They need to recover the data to the exact state as of 90 minutes ago.

They also cannot risk interrupting the current production database instance while investigators validate the restored data.

Which recovery strategy best meets these constraints?

Accepted Answer

Use point-in-time recovery (PITR) to restore to a new RDS DB instance as of 90 minutes ago, then validate and cut over after approval.. Point-in-time recovery (PITR) for Amazon RDS allows you to restore a DB instance to any second within the backup retention period, using automated backups and transaction logs. By restoring to a new RDS instance as of 90 minutes ago, you create an isolated copy for validation without affecting the production database. This meets both the recovery point objective (RPO) of 90 minutes and the constraint of no interruption to the current production instance.

Answer

Restore a manual snapshot and overwrite the existing production DB instance so the data matches exactly 90 minutes ago.

Answer

Wait for the next automated backup window and then restart the current DB instance to roll back changes automatically.

Answer

Use cross-region read replicas to rewind changes and promote the replica to become the writer immediately.

Question 10

You want to protect an Application Load Balancer (ALB) from common web exploits using AWS WAF. The application is not using CloudFront. Which AWS WAF deployment scope should you choose so the WAF rules apply to the ALB?

Accepted Answer

Use AWS WAF regional scope (associate the web ACL with the ALB resource). AWS WAF offers two deployment scopes: regional and CloudFront (global). Since the application is using an Application Load Balancer (ALB) without CloudFront, you must choose the regional scope. This allows you to associate the web ACL directly with the ALB resource, enabling AWS WAF to inspect HTTP/HTTPS requests for common web exploits like SQL injection and cross-site scripting (XSS) at the regional endpoint.

Answer

Use AWS WAF CloudFront (global) scope and associate the web ACL with the ALB

Answer

Use AWS Shield Advanced and rely on it to inspect payloads for SQL injection and XSS

Answer

Use security groups only, because they can detect SQL injection patterns in HTTP requests

Question 11

A mobile banking backend uses Amazon RDS for PostgreSQL. Application credentials must not be stored on the EC2 instances, and authentication should use short-lived credentials. What should the architect recommend? The design must avoid adding custom operational scripts.

Accepted Answer

IAM database authentication for RDS with an EC2 instance role. IAM database authentication for RDS allows EC2 instances to authenticate to PostgreSQL using a short-lived token generated via the IAM instance profile, eliminating the need to store credentials on the instance. The token is obtained by calling the RDS generate_db_auth_token API with the instance's IAM role, and it is valid for 15 minutes by default. This approach satisfies the requirement for short-lived credentials and avoids custom operational scripts.

Answer

Store the database password in user data

Answer

Use a security group rule that allows only application instances

Answer

Embed the database password in the AMI

Question 12

A team runs an application on Amazon EC2 that connects to an Aurora database. The database password must rotate automatically every 30 days, and the application should retrieve the current secret at runtime using an IAM role. Which AWS service is the best fit?

Accepted Answer

AWS Secrets Manager with rotation enabled.. AWS Secrets Manager is the best fit because it natively supports automatic rotation of database credentials on a schedule (e.g., every 30 days) and integrates directly with Amazon RDS/Aurora to update the password. The application can retrieve the current secret at runtime using an IAM role attached to the EC2 instance, without hardcoding credentials. Secrets Manager also provides built-in secret rotation with Lambda, ensuring zero downtime during password changes.

Answer

AWS Systems Manager Parameter Store standard parameters.

Answer

AWS KMS, because KMS stores credentials and rotates them automatically.

Answer

Amazon S3 with server-side encryption and versioning.

Question 13

Based on the exhibit, the company wants to lower CloudWatch and EC2 monitoring costs. Auditors require logs to be retained for 90 days, but operations only uses detailed per-instance metrics during rare troubleshooting events. Which change best reduces recurring cost while preserving the required visibility?

Accepted Answer

Set CloudWatch Logs retention to 90 days for all log groups, and switch EC2 monitoring from detailed to basic except during incidents.. It directly addresses the two cost drivers: CloudWatch Logs storage costs are minimized by setting a 90-day retention policy (matching the audit requirement), and EC2 detailed monitoring (1-minute metrics) is replaced with basic monitoring (5-minute metrics) during normal operations, with the ability to switch back to detailed only when needed for troubleshooting. This preserves the required log retention and the ability to obtain high-resolution metrics on demand, while eliminating the recurring cost of storing logs indefinitely and paying for detailed monitoring on every instance.

Answer

Disable CloudWatch Logs entirely and rely on application local files for 90 days.

Answer

Increase the number of CloudWatch alarms so that metrics are collected less expensively.

Answer

Export all logs to Amazon S3 immediately and keep detailed monitoring enabled on every instance.

Question 14

A service performs many repeated read requests for the same DynamoDB items. The reads are latency-sensitive, but the application can tolerate slightly stale data. Which AWS service is the best fit to reduce read latency?

Accepted Answer

Amazon DAX (DynamoDB Accelerator). Amazon DAX (DynamoDB Accelerator) is an in-memory cache specifically designed for DynamoDB. It reduces read latency from single-digit milliseconds to microseconds by caching frequently accessed items, and it supports eventually consistent reads, which aligns with the application's tolerance for slightly stale data. DAX handles repeated read requests without additional DynamoDB read capacity unit consumption, making it the optimal choice for this latency-sensitive workload.

Answer

Amazon S3 Select

Answer

Amazon SQS FIFO queue

Answer

AWS Lambda provisioned concurrency

Question 15

An application encrypts data directly with AWS KMS using an encryption context. Your KMS key policy includes a condition that allows kms:Decrypt only when the encryption context contains: "purpose" = "myapp-secrets" After a deployment, decryption fails. CloudTrail shows kms:Decrypt was called, but it was denied by the key policy due to the encryption context condition. What is the best fix?

Accepted Answer

Update the application code to supply the correct encryption context "purpose" = "myapp-secrets" when calling decrypt (and encrypt if rotating).. The decryption failure is directly caused by the application not supplying the required encryption context in the decrypt call. The KMS key policy condition explicitly requires the encryption context to include 'purpose'='myapp-secrets' for kms:Decrypt. Without this context, the request is denied regardless of IAM permissions. Updating the application code to pass the correct encryption context during both encrypt and decrypt operations resolves the issue.

Answer

Add kms:Decrypt to the IAM role attached to the application without changing the key policy.

Answer

Disable the encryption context condition in the KMS key policy to avoid future failures.

Answer

Rotate the KMS key immediately and re-encrypt all secrets with a different key ID.

Question 16

A ticket booking system uses Aurora MySQL. The company wants fast cross-Region disaster recovery with low RPO. Which architecture should be considered?

Accepted Answer

Aurora Global Database. Aurora Global Database is designed for cross-Region disaster recovery with a typical RPO of 1 second or less, using storage-based replication that does not impact database performance. This meets the requirement for fast failover and low data loss, unlike manual snapshot-based approaches which have higher RPO and slower recovery.

Answer

A single-AZ Aurora cluster

Answer

An ElastiCache Redis replica

Answer

Manual snapshots copied monthly

Question 17

Based on the exhibit, the database must fail over automatically if the primary Availability Zone goes down. Which solution should the architect choose?

Accepted Answer

Convert the database to a Multi-AZ RDS deployment.. A Multi-AZ RDS deployment automatically provisions and maintains a synchronous standby replica in a different Availability Zone. If the primary AZ fails, Amazon RDS automatically fails over to the standby, typically within 60–120 seconds, without requiring manual intervention or changes to the application connection string.

Answer

Create a read replica in the same Availability Zone as the primary database.

Answer

Increase the backup retention period to 35 days.

Answer

Move the database to an EC2 instance with an attached EBS volume.

Question 18

A team runs a CPU-intensive image processing service on Amazon EC2. The service spends most of its time resizing and compressing images, and the team wants the best price-performance starting point for compute-heavy work. Which EC2 instance family should they choose?

Accepted Answer

Compute optimized instances. Compute optimized instances (C family) are designed for workloads that benefit from high-performance processors, such as batch processing, media transcoding, and image processing. Since the team's service is CPU-intensive (resizing and compressing images), the C family provides the best price-performance starting point for compute-heavy work.

Answer

Memory optimized instances

Answer

Storage optimized instances

Answer

General purpose instances

Question 19

A Lambda function behind an API needs consistent low latency. Traffic normally drops to near zero, then spikes several times per hour. During spikes, the p95 latency often spikes above 800 ms due to cold starts. The team wants to keep using Lambda (no containers) but minimize cold start impact during predictable spikes. What is the best AWS configuration to meet this goal?

Accepted Answer

Enable Lambda provisioned concurrency on a published function alias and set the minimum provisioned instances to the baseline expected during spikes.. Provisioned concurrency initializes a specified number of execution environments in advance, keeping them warm and ready to handle requests instantly. By setting the minimum provisioned instances to the baseline expected during spikes, the function avoids cold starts for those requests, ensuring p95 latency stays low even when traffic surges from near zero.

Answer

Increase the function memory size to the maximum and rely on the larger memory to eliminate cold starts.

Answer

Configure an ALB with target group health checks to keep Lambda warm by sending periodic requests.

Answer

Turn on AWS CloudTrail data events to monitor cold start frequency and tune the runtime accordingly.

Question 20

A warehouse integration service receives bursts of orders that sometimes overwhelm a downstream fulfilment service. The architecture must absorb spikes and retry processing without losing requests. Which service should be placed between the web tier and fulfilment workers? The design must avoid adding custom operational scripts.

Accepted Answer

Amazon SQS queue. Amazon SQS is the correct choice because it acts as a durable, scalable message buffer that decouples the web tier from the fulfilment workers. When order bursts arrive, messages are stored reliably in the queue, and workers can poll at their own pace, retrying failed messages automatically without any custom scripts. This pattern absorbs spikes and ensures no requests are lost, meeting the requirement for a fully managed, serverless integration.

Answer

AWS WAF

Answer

Amazon Route 53 weighted routing

Answer

Amazon CloudFront