DVA-C02 Development with AWS Services Practice Test 8 — 15 Questions

Question 1

A developer is building a data processing pipeline that uses AWS Lambda to process files uploaded to an S3 bucket. The S3 bucket receives thousands of files per second, and the developer wants to minimize processing latency. Which approach should the developer use to trigger the Lambda function?

Accepted Answer

Configure S3 event notifications to directly invoke the Lambda function.. Option B is correct because S3 event notifications can directly invoke Lambda asynchronously, providing low-latency processing. Option A (SQS) adds polling latency. Option C (CloudWatch Events) is for scheduled events, not S3 events. Option D (SNS) adds an extra hop and requires subscription.

Answer

Configure an SQS queue and have the Lambda function poll the queue for S3 event notifications.

Answer

Use Amazon CloudWatch Events to trigger the Lambda function on a schedule.

Answer

Publish S3 events to an SNS topic and subscribe the Lambda function to that topic.

Question 2

A developer is troubleshooting an AWS Lambda function that occasionally fails with a timeout error. The function makes HTTP requests to external APIs. The function's current timeout setting is 30 seconds. The developer wants to implement a solution that reduces the chance of timeouts without increasing the Lambda timeout. Which approach should the developer take?

Accepted Answer

Implement retry logic with exponential backoff in the Lambda function code.. Option A is correct because implementing retry logic with exponential backoff allows the function to handle transient failures without timing out. Option B (increase timeout) contradicts the requirement. Option C (provisioned concurrency) addresses cold starts, not timeouts. Option D (async invocation) does not change the execution time.

Answer

Configure the Lambda function to be invoked asynchronously.

Answer

Enable provisioned concurrency on the Lambda function.

Answer

Increase the Lambda function timeout to 5 minutes.

Question 3

A company is deploying a containerized application on Amazon ECS with Fargate launch type. The application needs to store sensitive configuration data such as database passwords. The developer must ensure that the secrets are encrypted at rest and in transit, and that they are rotated automatically. Which solution should the developer use?

Accepted Answer

Store secrets in AWS Secrets Manager and use a Lambda function to rotate the secrets.. Option D is correct because AWS Secrets Manager provides automatic rotation, encryption at rest, and integration with ECS for secure retrieval. Option A (Parameter Store with KMS) does not support automatic rotation. Option B (Secrets Manager with Lambda rotation) is essentially correct but the Lambda function is needed for custom rotation; however, Secrets Manager can manage rotation automatically with built-in rotation for AWS services. Option C (EC2 Systems Manager) is not for secrets management.

Answer

Store secrets in AWS Secrets Manager and enable automatic rotation.

Answer

Store secrets in AWS Systems Manager Parameter Store with a secure string parameter encrypted using AWS KMS.

Answer

Store secrets in an encrypted S3 bucket and retrieve them in the task definition.

Question 4

A developer wants to share an Amazon Machine Image (AMI) from one AWS account to another. The AMI is backed by Amazon EBS snapshots. What must the developer do to ensure the target account can launch an EC2 instance from the AMI?

Accepted Answer

Modify the AMI permissions to allow the target account and share the underlying EBS snapshots.. Option A is correct because the AMI must be shared with the target account, and the EBS snapshots must be shared as well. Option B (copy to target account) is not necessary. Option C (public) is not required. Option D (encryption key) is only needed if the snapshots are encrypted.

Answer

Copy the AMI to the target account's region and share the AMI.

Answer

Make the AMI public and share the EBS snapshots.

Answer

Share the KMS key used to encrypt the EBS snapshots with the target account.

Question 5

A developer is using Amazon S3 to store application logs. The logs are generated every hour and must be retained for 90 days. After 90 days, the logs should be deleted automatically. Which S3 lifecycle policy should the developer configure?

Accepted Answer

Expire objects after 90 days.. Option B is correct because an expiration action after 90 days will delete the objects. Option A (transition to Glacier after 90 days) does not delete. Option C (expire after 30 days) deletes too early. Option D (transition to S3 Standard-IA and expire after 90 days) is valid but unnecessary; a single expiration action is simpler.

Answer

Expire objects after 30 days.

Answer

Transition objects to Amazon S3 Glacier after 90 days.

Answer

Transition objects to S3 Standard-IA after 30 days and expire after 90 days.

Question 6

A developer is debugging an AWS Lambda function that processes messages from an Amazon SQS queue. The function is failing with an error when processing certain messages. The developer wants to isolate the failed messages for later analysis without losing them. What should the developer do?

Accepted Answer

Configure a dead-letter queue (DLQ) for the SQS queue.. Option C is correct because a dead-letter queue (DLQ) on the SQS queue will capture messages that cannot be processed, allowing the function to continue processing other messages. Option A (increase visibility timeout) does not isolate failed messages. Option B (log and ignore) loses the messages. Option D (use SNS) is not a standard pattern for this issue.

Answer

Publish the failed messages to an SNS topic for later processing.

Answer

Log the error and delete the message from the queue.

Answer

Increase the visibility timeout of the SQS queue.

Question 7

Which TWO AWS services can be used to store and retrieve application configuration data? (Choose two.)

Accepted Answer

AWS AppConfig. Option B (AWS AppConfig) and Option D (AWS Systems Manager Parameter Store) are correct. AppConfig is designed for application configuration, and Parameter Store can store configuration parameters. Option A (Secrets Manager) is for secrets, not general config. Option C (S3) is for objects. Option E (CloudFormation) is for infrastructure as code.

Answer

AWS Secrets Manager

Answer

Amazon S3

Answer

AWS CloudFormation

Question 8

Which THREE actions can be performed using AWS Lambda and Amazon S3 event notifications? (Choose three.)

Accepted Answer

Resize an image when a new image is uploaded to an S3 bucket.. Options A, B, and C are correct. S3 event notifications can trigger Lambda on PUT, POST, DELETE, etc. Option D (pre-signed URL generation) is not an event; it's a client action. Option E (versioning) is a bucket property, not triggered by events.

Answer

Generate a pre-signed URL for an object.

Answer

Enable versioning on the S3 bucket.

Question 9

Which TWO AWS services can be used to send messages between microservices in a decoupled manner? (Choose two.)

Accepted Answer

Amazon SQS. Option A (Amazon SQS) and Option B (Amazon SNS) are correct. SQS is a message queue, SNS is a pub/sub messaging service. Option C (Amazon Kinesis Data Streams) is for real-time streaming, not typically for simple messaging. Option D (AWS Lambda) is a compute service. Option E (Amazon MQ) is a managed message broker, but SQS and SNS are the primary decoupling services.

Answer

AWS Lambda

Answer

Amazon MQ

Answer

Amazon Kinesis Data Streams

Question 10

An IAM policy attached to an IAM user. What is the effect of this policy on the user's ability to delete objects in the bucket my-bucket?

Accepted Answer

The user is denied the ability to delete objects regardless of source IP.. Option B is correct because the Deny statement has a condition that only denies the action when the source IP is NOT in the specified range. So if the user's IP is in 192.0.2.0/24, the Deny does not apply, and since there is no explicit Allow for DeleteObject, the default implicit Deny applies, so deletion is denied regardless. Actually, need to analyze: The Deny applies when source IP is not in the range. If the source IP is in the range, the Deny condition is not met, so the Deny statement does not apply. However, there is no Allow for DeleteObject, so the action is implicitly denied. Therefore, deletion is always denied. If there were an Allow, then the Allow would take effect when the Deny doesn't apply. But here there is no Allow, so it's denied always. So answer B is correct: the user is denied because there is no Allow statement for DeleteObject.

Answer

The user can delete objects from any IP address.

Answer

The user can delete objects only if the source IP is not 192.0.2.0/24.

Answer

The user can delete objects only if the source IP is 192.0.2.0/24.

Question 11

An IAM policy attached to an AWS Lambda function's execution role. What actions can this Lambda function perform?

Accepted Answer

Invoke the specified Lambda function and send messages to the SQS queue.. Option C is correct. The policy allows invoking a specific Lambda function (which may be itself or another) and sending messages to a specific SQS queue. It does not allow receiving messages. Option A (only invoke) is incomplete. Option B (only send) is incomplete. Option D (invoke and receive) is incorrect because receive is not allowed.

Answer

Invoke the specified Lambda function and receive messages from the SQS queue.

Answer

Send messages to the SQS queue and invoke any Lambda function.

Answer

Invoke the specified Lambda function and receive messages from the SQS queue.

Question 12

A developer runs the AWS CLI command to invoke a Lambda function synchronously. What does the output indicate?

Accepted Answer

The Lambda function executed successfully and returned a response.. Option A is correct. The StatusCode 200 indicates the invocation was successful, and the response contains the Lambda function's output. Option B (validation error) would return a different status code. Option C (timeout) would return a timeout error. Option D (function not found) would return 404.

Answer

The Lambda function failed validation.

Answer

The Lambda function was not found.

Answer

The Lambda function timed out.

Question 13

A developer wants to store application logs in Amazon S3 with automatic transition to Glacier after 30 days and deletion after 365 days. Which S3 feature should be used?

Accepted Answer

S3 Lifecycle configuration. S3 Lifecycle policies automate transitioning objects between storage classes and expiring them. Option A is correct.

Answer

S3 Object Lock

Answer

S3 Replication

Answer

S3 Event Notifications

Question 14

A developer is using AWS Lambda with an Amazon RDS MySQL database. The Lambda function frequently times out when connecting to the database. What is the MOST likely cause?

Accepted Answer

The Lambda function is not attached to the same VPC as the RDS instance. Lambda functions in a VPC require a VPC endpoint for internet access or NAT gateway; without it, they cannot reach RDS if the RDS is in a private subnet. Option C is correct.

Answer

The Lambda function is not configured with enough memory

Answer

The Lambda function is not using a reserved concurrency limit

Answer

The Lambda function's execution role lacks RDS permissions

Question 15

A developer is building a serverless application using AWS Lambda and Amazon API Gateway. The developer wants to enable caching for API responses to reduce latency and cost. Which step is REQUIRED to enable caching?

Accepted Answer

Create a cache cluster in API Gateway for the stage. To enable API Gateway caching, you must create a cache cluster on the stage level, which incurs additional cost. Option B is correct.

Answer

Enable caching in the Lambda function code

Answer

Set the TTL in the API Gateway method request integration

Answer

Use Amazon ElastiCache and modify the Lambda function to check cache