SAA-C03 SAA-C03 practice test

A content publishing system uses Lambda functions that call an unreliable third-party API. Failed events must be retained for later investigation after retries are exhausted. What should be configured? The team wants the control to be enforceable during normal operations.

Trap 1: Lambda reserved concurrency set to zero

Reserved concurrency of zero stops processing and does not preserve failed events as an error-handling strategy.

Trap 2: A larger deployment package

Package size does not affect failed-event capture.

Trap 3: CloudFront error pages

CloudFront does not manage Lambda asynchronous retry failures.

A
Lambda reserved concurrency set to zero
Why wrong: Reserved concurrency of zero stops processing and does not preserve failed events as an error-handling strategy.
B
A larger deployment package
Why wrong: Package size does not affect failed-event capture.
C
CloudFront error pages
Why wrong: CloudFront does not manage Lambda asynchronous retry failures.
D
A Lambda dead-letter queue or failure destination
A DLQ or asynchronous failure destination captures failed events after retry attempts.

Question 2mediummulti select

A startup runs two EC2-based workloads in the same AWS Region. Its customer-facing API is always on, and its nightly video transcoding fleet can restart jobs from checkpoints if an instance is interrupted. The finance team wants the lowest monthly compute cost without changing the application design. Which two actions should the team take? Select two.

Trap 1: Purchase an All Upfront Reserved Instance for the transcoding fleet…

Reserved Instances fit steady, predictable usage, but this batch fleet is interruption-tolerant and variable.

Trap 2: Increase the API instance size so CPU utilization stays below 30…

Larger instances raise cost; right sizing should reduce waste, not add extra unused capacity.

Trap 3: Move the API tier to Dedicated Hosts to improve isolation and lower…

Dedicated Hosts usually increase cost and are used for licensing or compliance, not savings.

A
Purchase an All Upfront Reserved Instance for the transcoding fleet only.
Why wrong: Reserved Instances fit steady, predictable usage, but this batch fleet is interruption-tolerant and variable.
B
Buy a Compute Savings Plan to cover the always-on API baseline usage.
Savings Plans reduce cost for consistent compute usage and are well suited to the always-on API.
C
Run the transcoding fleet on Spot Instances because interrupted jobs can resume from checkpoints.
Spot Instances are ideal for flexible batch processing when interruptions are acceptable and checkpointing exists.
D
Increase the API instance size so CPU utilization stays below 30 percent.
Why wrong: Larger instances raise cost; right sizing should reduce waste, not add extra unused capacity.
E
Move the API tier to Dedicated Hosts to improve isolation and lower spend.
Why wrong: Dedicated Hosts usually increase cost and are used for licensing or compliance, not savings.

Read the full NAT/PAT explanation →

Question 3hardmultiple choice

A warehouse integration service must use shared file storage across Linux EC2 instances in multiple Availability Zones. The storage must remain available during an AZ failure. Which service should be used? The architecture review board prefers a managed AWS-native control.

Trap 1: S3 mounted as a POSIX file system without a file gateway

S3 is object storage and does not provide native POSIX shared file semantics.

Trap 2: Instance store volumes

Instance store is ephemeral and tied to a single instance.

Trap 3: An EBS volume attached to all instances

A standard EBS volume is zonal and cannot be attached broadly as shared file storage.

A
Amazon EFS with mount targets in multiple Availability Zones
EFS is regional file storage and supports mount targets across AZs.
B
S3 mounted as a POSIX file system without a file gateway
Why wrong: S3 is object storage and does not provide native POSIX shared file semantics.
C
Instance store volumes
Why wrong: Instance store is ephemeral and tied to a single instance.
D
An EBS volume attached to all instances
Why wrong: A standard EBS volume is zonal and cannot be attached broadly as shared file storage.

Question 4easymultiple choice

A team runs a stateless web app on Amazon EC2 behind an Application Load Balancer. During traffic spikes, new EC2 instances take several minutes to finish bootstrapping before they can receive traffic. Which Auto Scaling configuration most directly reduces the time until additional capacity is available?

Trap 1: Increase the ALB target group deregistration delay.

Deregistration delay affects how long old instances stay in service during scale-in, not how quickly new instances become available.

Trap 2: Reduce the Auto Scaling group minimum size to one instance.

Lowering minimum capacity can reduce cost, but it does not make additional instances available faster during demand spikes.

Trap 3: Replace the Application Load Balancer with a Network Load Balancer.

A Network Load Balancer does not solve instance bootstrapping time and is not the main lever for faster scale-out readiness.

A
Increase the ALB target group deregistration delay.
Why wrong: Deregistration delay affects how long old instances stay in service during scale-in, not how quickly new instances become available.
B
Use an Auto Scaling warm pool so pre-initialized instances are ready to enter service.
Warm pools keep instances pre-launched and initialized, which reduces the time needed to add capacity during spikes.
C
Reduce the Auto Scaling group minimum size to one instance.
Why wrong: Lowering minimum capacity can reduce cost, but it does not make additional instances available faster during demand spikes.
D
Replace the Application Load Balancer with a Network Load Balancer.
Why wrong: A Network Load Balancer does not solve instance bootstrapping time and is not the main lever for faster scale-out readiness.

Read the full NAT/PAT explanation →

Question 5mediummulti select

A service in private subnets downloads product images from Amazon S3 and stores job state in DynamoDB. A NAT Gateway is currently the only route to AWS services, and the monthly bill is dominated by NAT data processing charges. Which two changes will most directly reduce that cost? Select two.

Trap 1: Add an internet gateway and move the instances into public subnets.

This changes the routing model and security exposure, but it does not reduce the amount of traffic the application sends to AWS services. It also does nothing to remove NAT-related charges for private service access.

Trap 2: Replace the NAT Gateway with a Site-to-Site VPN connection.

A VPN is meant for connectivity to on-premises or external networks. It does not eliminate the need to reach S3 and DynamoDB privately, so it does not directly solve the NAT data-processing-cost problem.

Trap 3: Create an interface endpoint for S3 instead of a gateway endpoint.

An interface endpoint can work for some S3 use cases, but it adds hourly and data-processing charges. For the specific goal of lowering NAT charges for S3 access from private subnets, the S3 gateway endpoint is the lower-cost choice.

A
Create a gateway VPC endpoint for Amazon S3.
An S3 gateway endpoint routes S3 traffic over the AWS private network instead of through the NAT Gateway. That removes NAT data processing charges for the S3 downloads and is one of the most direct cost optimizations for private-subnet workloads.
B
Create a gateway VPC endpoint for Amazon DynamoDB.
DynamoDB also supports a gateway endpoint, which keeps table traffic off the NAT Gateway path. Using the endpoint avoids both NAT data processing fees and the need to hairpin private AWS API calls through internet egress.
C
Add an internet gateway and move the instances into public subnets.
Why wrong: This changes the routing model and security exposure, but it does not reduce the amount of traffic the application sends to AWS services. It also does nothing to remove NAT-related charges for private service access.
D
Replace the NAT Gateway with a Site-to-Site VPN connection.
Why wrong: A VPN is meant for connectivity to on-premises or external networks. It does not eliminate the need to reach S3 and DynamoDB privately, so it does not directly solve the NAT data-processing-cost problem.
E
Create an interface endpoint for S3 instead of a gateway endpoint.
Why wrong: An interface endpoint can work for some S3 use cases, but it adds hourly and data-processing charges. For the specific goal of lowering NAT charges for S3 access from private subnets, the S3 gateway endpoint is the lower-cost choice.

Question 6mediummulti select

A static site is hosted in Amazon S3 and delivered by CloudFront. After a frontend release, the same JavaScript bundles are fetched repeatedly from the origin. Logs show that requests include unneeded query strings and cookies, which prevent cache reuse. Which two changes should the team make to reduce origin traffic and cost? Select two.

Trap 1: Increase the size of the S3 bucket.

Bucket size does not improve cache reuse or reduce request costs. The issue is cacheability, not storage capacity.

Trap 2: Place an Application Load Balancer in front of S3.

An ALB is not used as a front end for static S3 content in this pattern. It adds unnecessary infrastructure and does not address the cache key problem.

Trap 3: Disable caching so clients always get the latest files.

Disabling caching guarantees more origin traffic and higher cost. The deployment already uses versioned assets, so cache efficiency should increase rather than disappear.

A
Configure a CloudFront cache policy that forwards only the query strings, headers, and cookies the app actually needs.
Reducing the cache key to only required values increases cache hit ratio and lowers origin fetches. CloudFront can reuse responses more effectively when unnecessary request data is not forwarded.
B
Use versioned file names for static assets and set a long TTL for immutable objects.
Versioned filenames let you cache assets aggressively without risking stale content after deployments. Long TTLs reduce repeated origin requests and lower both transfer and request costs.
C
Increase the size of the S3 bucket.
Why wrong: Bucket size does not improve cache reuse or reduce request costs. The issue is cacheability, not storage capacity.
D
Place an Application Load Balancer in front of S3.
Why wrong: An ALB is not used as a front end for static S3 content in this pattern. It adds unnecessary infrastructure and does not address the cache key problem.
E
Disable caching so clients always get the latest files.
Why wrong: Disabling caching guarantees more origin traffic and higher cost. The deployment already uses versioned assets, so cache efficiency should increase rather than disappear.