Amazon DVA-C02 Exam Questions Instant Access

Question 1

A developer is investigating an issue in part of a company's application. In the application messages are sent to an Amazon Simple Queue Service (Amazon SQS) queue The AWS Lambda function polls messages from the SQS queue and sends email messages by using Amazon Simple Email Service (Amazon SES) Users have been receiving duplicate email messages during periods of high traffic.

Which reasons could explain the duplicate email messages? (Select TWO.)

AStandard SQS queues support at-least-once message delivery

BStandard SQS queues support exactly-once processing, so the duplicate email messages are because of user error.

CAmazon SES has the DomainKeys Identified Mail (DKIM) authentication incorrectly configured

DThe SQS queue's visibility timeout is lower than or the same as the Lambda function's timeout.

EThe Amazon SES bounce rate metric is too high.

Answer : A

SQS Delivery Behavior:Standard SQS queues guarantee at-least-once delivery, meaning messages may be processed more than once. This can lead to duplicate emails in this scenario.

Visibility Timeout:If the visibility timeout on the SQS queue is too short, a message might become visible for another consumer before the first Lambda function finishes processing it. This can also lead to duplicates.

Amazon SQS Delivery Semantics:[invalid URL removed]

Amazon SQS Visibility Timeout:https://docs.aws.amazon.com/AWSSimpleQueueService/latest/SQSDeveloperGuide/sqs-visibility-timeout.html

Question 2

An application that runs on AWS receives messages from an Amazon Simple Queue Service (Amazon SQS) queue and processes the messages in batches. The

application sends the data to another SQS queue to be consumed by another legacy application. The legacy system can take up to 5 minutes to process some transaction data.

A developer wants to ensure that there are no out-of-order updates in the legacy system. The developer cannot alter the behavior of the legacy system.

Which solution will meet these requirements?

AUse an SQS FIFO queue. Configure the visibility timeout value.

BUse an SQS standard queue with a SendMessageBatchRequestEntry data type. Configure the DelaySeconds values.

CUse an SQS standard queue with a SendMessageBatchRequestEntry data type. Configure the visibility timeout value.

DUse an SQS FIFO queue. Configure the DelaySeconds value.

Answer : A

An SQS FIFO queue is a type of queue that preserves the order of messages and ensures that each message is delivered and processed only once1. This is suitable for the scenario where the developer wants to ensure that there are no out-of-order updates in the legacy system.

The visibility timeout value is the amount of time that a message is invisible in the queue after a consumer receives it2. This prevents other consumers from processing the same message simultaneously.If the consumer does not delete the message before the visibility timeout expires, the message becomes visible again and another consumer can receive it2.

In this scenario, the developer needs to configure the visibility timeout value to be longer than the maximum processing time of the legacy system, which is 5 minutes. This will ensure that the message remains invisible in the queue until the legacy system finishes processing it and deletes it. This will prevent duplicate or out-of-order processing of messages by the legacy system.

Question 3

A developer created reusable code that several AWS Lambda functions need to use. The developer bundled the code into a .zip archive. The developer needs to deploy the code to AWS and update the Lambda functions to use the code.

Which solution will meet this requirement in the MOST operationally efficient way?

AUpload the .zip archive to Amazon S3. Configure an import path on the Lambda functions to point to the .zip archive.

BCreate a new Lambda function that contains and runs the shared code. Update the existing Lambda functions to invoke the new Lambda function synchronously.

CCreate a Lambda layer that contains the .zip archive. Attach the Lambda layer to the Lambda functions.

DCreate a Lambda container image that includes the shared code. Use the container image as a Lambda base image for all the functions.

Answer : C

A Lambda layer is the correct operationally efficient solution because layers are specifically designed to package reusable code, libraries, custom runtimes, or configuration files separately from function code. The developer can publish the shared .zip archive as a layer version and attach that layer to multiple Lambda functions. This avoids copying the same dependency into every deployment package and centralizes dependency management. Amazon S3 alone does not create an importable runtime dependency path for Lambda. A separate Lambda function would add synchronous invocation latency and coupling. A container image could work for container-based functions, but it is heavier and unnecessary when the code is already packaged as a .zip dependency. AWS documentation states that layers are used to separate reusable dependencies from function code and add them to functions. (AWS Documentation)

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Question 4

A company's application has an AWS Lambda function that processes messages from loT devices. The company wants to monitor the Lambda function to ensure that the Lambda function is meeting its required service level agreement (SLA).

A developer must implement a solution to determine the application's throughput in near real time. The throughput must be based on the number of messages that the Lambda function receives and processes in a given time period. The Lambda function performs initialization and post-processing steps that must not factor into the throughput measurement.

What should the developer do to meet these requirements?

AUse the Lambda function's ConcurrentExecutions metric in Amazon CloudWatch to measure the throughput.

BModify the application to log the calculated throughput to Amazon CloudWatch Logs. Use Amazon EventBridge to invoke a separate Lambda function to process the logs on a schedule.

CModify the application to publish custom Amazon CloudWatch metrics when the Lambda function receives and processes each message. Use the metrics to calculate the throughput.

DUse the Lambda function's Invocations metric and Duration metric to calculate the throughput in Amazon CloudWatch.

Answer : C

Question 5

A company has a large amount of data in an Amazon DynamoDB table. A large batch of data is appended to the table once each day. The company wants a solution that will make all the existing and future data in DynamoDB available for analytics on a long-term basis.

Which solution meets these requirements with the LEAST operational overhead?

AConfigure DynamoDB incremental exports to Amazon S3.

BConfigure Amazon DynamoDB Streams to write records to Amazon S3.

CConfigure Amazon EMR to copy DynamoDB data to Amazon S3.

DConfigure Amazon EMR to copy DynamoDB data to Hadoop Distributed File System (HDFS).

Answer : A

Why Option A is Correct:DynamoDB supports incremental exports to Amazon S3 natively, making data analytics-ready with minimal operational overhead.

Why Other Options are Incorrect:

Option B: DynamoDB Streams require additional processing logic to write to S3, increasing complexity.

Option C & D: Using EMR for data movement adds unnecessary operational overhead compared to native exports.

AWS Documentation Reference:

DynamoDB Exports to S3

Question 6

A company had an Amazon RDS for MySQL DB instance that was named mysql-db. The DB instance was deleted within the past 90 days. A developer needs to find which 1AM user or role deleted the DB instance in the AWS environment. Which solution will provide this information?

ARetrieve the AWS CloudTrail events for the resource mysql-db where the event name is DeleteDBInstance. Inspect each event.

BRetrieve the Amazon CloudWatch log events from the most recent log stream within the rds/mysql-db log group. Inspect the log events.

CRetrieve the AWS X-Ray trace summaries. Filter by services with the name mysql-db. Inspect the ErrorRootCauses values within each summary.

DRetrieve the AWS Systems Manager deletions inventory Filter the inventory by deletions that have a TypeName value of RDS. Inspect the deletion details.

Answer : A

Question 7

A developer is building a solution to give an application that runs on an ecommerce platform the ability to send notifications. The application needs to call an API to send thousands of notifications each second to an HTTP endpoint. The notifications must be delivered in order. The developer must be able to filter out some of the notifications before sending them to the endpoint. Which solution will meet these requirements?

ACreate an Amazon Data Firehose stream that uses Direct PUT as the source. Set the URL of the HTTP endpoint as the destination.

BCreate an Amazon SQS standard queue and an Amazon SNS FIFO topic. Create an AWS Lambda function and use the HTTP client to send the notifications. Set the SQS queue as the event source for the Lambda function and attach filter criteria.

CCreate an Amazon SNS topic in high throughput mode. Subscribe the URL of the HTTP endpoint to the SNS topic. Configure a subscription filter policy.

DCreate an Amazon EventBridge rule. Create an EventBridge pipe and set the rule as the target. Configure a filter for the pipe. Set the URL of the HTTP endpoint as the rule's API destination endpoint.

Answer : C

The correct answer is C because Amazon SNS FIFO topics are designed for applications that require both message ordering and deduplication, and high throughput mode extends the throughput capability to support large-scale workloads such as sending thousands of notifications per second. This directly matches the requirement for ordered notification delivery at very high scale.

The requirement to filter out some notifications before sending them to the HTTP endpoint is also handled natively by SNS subscription filter policies. With a filter policy, only messages with matching message attributes are delivered to the subscribed endpoint. This means the application can publish all notification events to the SNS topic, while SNS ensures that only relevant notifications are forwarded to the HTTP subscriber. This avoids unnecessary downstream traffic and reduces custom logic.

Option A is incorrect because Amazon Data Firehose is intended primarily for streaming data delivery to analytics and storage destinations, not for ordered notification delivery to HTTP endpoints with filtering requirements. Option B is incorrect because Amazon SQS standard queues do not preserve strict ordering. Also, this design adds Lambda processing complexity and does not align as cleanly with native FIFO and filtering capabilities. Option D is not the best choice because EventBridge supports filtering and API destinations, but it does not provide the same straightforward FIFO ordered delivery guarantee required here.

Therefore, Amazon SNS FIFO in high throughput mode with an HTTP subscription and subscription filter policy is the AWS service combination that best satisfies all the stated requirements.

Amazon AWS Certified Developer - Associate DVA-C02 Exam Questions