DVA-C02 Development with AWS Services Practice Test 19 — 15 Questions

Question 1

A developer is deploying a serverless application using the AWS Serverless Application Model (SAM). The application includes an API Gateway REST API and a Lambda function. The developer wants to enable access logging for the API Gateway. Which THREE resources or configurations are required? (Choose THREE.)

Accepted Answer

A stage with access logging enabled in the API Gateway.. Options A, B, and D are correct. Option A sets up a log group. Option B configures the IAM role for API Gateway to write logs. Option D enables access logging. Option C is not required because Lambda function logs are separate. Option E is not required because Lambda execution role is for Lambda, not API Gateway logging.

Answer

A Lambda function that processes the access logs.

Answer

An IAM role for the Lambda function with logs:PutLogEvents permission.

Question 2

A company runs a data processing pipeline using AWS Step Functions. The pipeline starts with a task that reads a CSV file from Amazon S3 and then fans out to multiple parallel Lambda functions for data transformation. The final step aggregates the results and writes to an Amazon DynamoDB table. Recently, the pipeline has been failing intermittently with 'StateMachineExecutionLimitExceeded' errors. The development team has already increased the execution history limit to the maximum. The pipeline runs about 500 executions per day. Meanwhile, the operations team reports that some executions are timing out after 5 minutes, even though each Lambda function completes within 30 seconds. The Step Function definition uses a Map state with a max concurrency of 20. The developer needs to fix both issues. Which combination of actions should the developer take? (Choose the BEST option.)

Accepted Answer

Reduce the max concurrency of the Map state and increase the task execution timeout in the Step Function definition.. Option A is correct because reducing max concurrency and increasing task timeout addresses both state machine execution limits and timeouts. Option B is wrong because increasing map concurrency would worsen throttling. Option C is wrong because splitting into multiple state machines does not address task timeouts. Option D is wrong because Lambda reserved concurrency does not prevent state machine throttling.

Answer

Split the pipeline into multiple smaller Step Functions and chain them together.

Answer

Increase the max concurrency of the Map state and add a retry policy.

Answer

Set a Lambda reserved concurrency for the transformation functions to 100.

Question 3

A developer is building a mobile backend using Amazon API Gateway and AWS Lambda. The API has a single endpoint that accepts POST requests with a JSON payload and stores the data in an Amazon DynamoDB table. The developer wants to implement caching to reduce latency and costs. The data is user-specific and should not be shared between users. The developer configures API Gateway caching with a TTL of 300 seconds. After testing, the developer notices that users are seeing other users' data. What should the developer do to fix this issue?

Accepted Answer

Enable cache key parameters in API Gateway, such as the Authorization header.. Option C is correct because enabling cache keys for headers like Authorization ensures cached responses are per-user. Option A is wrong because disabling caching removes benefits. Option B is wrong because DynamoDB is for storage, not caching. Option D is wrong because Lambda@Edge is for CloudFront, not API Gateway caching.

Answer

Store cached responses in DynamoDB and retrieve them based on user ID.

Answer

Use Lambda@Edge to cache responses at the CloudFront level.

Answer

Disable API Gateway caching and use DynamoDB Accelerator (DAX) instead.

Question 4

A company is using AWS Lambda functions behind an Amazon API Gateway REST API. Users report intermittent 503 errors. The Lambda function code appears correct. Which action is MOST likely to resolve the issue?

Accepted Answer

Request a service quota increase for Lambda concurrent executions.. Option D is correct because Lambda concurrent execution limits can cause throttling, leading to 503 errors. Increasing the limit provides more capacity. Option A is wrong because Lambda timeout errors cause 504, not 503. Option B is wrong because API Gateway throttling (default 10,000 rps) is usually not the cause at low rates. Option C is wrong because memory increase helps performance but not concurrency limits.

Answer

Increase the Lambda function memory allocation.

Answer

Increase the Lambda function timeout.

Answer

Increase the API Gateway throttling limits.

Question 5

A developer is building a serverless application using AWS Lambda and Amazon DynamoDB. The Lambda function reads from a DynamoDB table. The function fails with a timeout error when processing large items. What is the MOST efficient solution?

Accepted Answer

Increase the Lambda function timeout.. Option C is correct because increasing Lambda timeout gives more time for large item processing. Option A is wrong because provisioned concurrency reduces cold starts but not timeouts. Option B is wrong because increasing memory also increases CPU, but the primary issue is the timeout limit. Option D is wrong because increasing DynamoDB RCUs addresses throttling, not timeouts.

Answer

Increase the Lambda function memory.

Answer

Enable Lambda provisioned concurrency.

Answer

Increase the DynamoDB read capacity units.

Question 6

A developer attached the above IAM policy to an IAM user. The user reports being denied access to objects in the S3 bucket 'my-bucket' from an IP address in the 10.0.0.0/24 range. What is the MOST likely cause?

Accepted Answer

The IP address range 10.0.0.0/24 is a private range not seen by S3.. Option B is correct because IAM policies use the key 'aws:SourceIp' for source IP conditions, but the policy uses 'IpAddress' which is incorrect; the correct condition key is 'IpAddress' but the operator 'IpAddress' is valid. However, the condition key should be 'aws:SourceIp' (the key used in the policy is correct). Actually, the issue is that IAM policies cannot restrict based on source IP for S3 actions in all cases; S3 bucket policies support it, but IAM user policies also support 'aws:SourceIp'. The problem is that the IP address range 10.0.0.0/24 is a private IP range. S3 does not see the private IP of the client when accessed from within a VPC; it sees the public IP or VPC endpoint IP. Therefore, the condition never matches, causing denial. Option B is correct because private IPs are not seen by S3.

Answer

The Resource ARN is missing the bucket name.

Answer

The bucket policy also denies access.

Answer

The condition should use 'aws:VpcSourceIp' instead.

Question 7

A developer is deploying a web application on AWS Elastic Beanstalk. The application requires a fixed IP address for outbound traffic to a third-party API. What is the MOST cost-effective solution?

Accepted Answer

Launch the environment in a VPC with a NAT Gateway in a public subnet.. Option A is correct because a NAT Gateway in a public subnet provides a fixed public IP for outbound traffic from EC2 instances in private subnets. Option B is wrong because an Internet Gateway does not provide a fixed IP. Option C is wrong because Elastic IPs attached to instances are not managed by Elastic Beanstalk easily. Option D is wrong because a VPC endpoint is for private connectivity to AWS services, not third-party APIs.

Answer

Attach an Internet Gateway to the VPC.

Answer

Use a VPC endpoint for the third-party API.

Answer

Assign an Elastic IP to each EC2 instance.

Question 8

A developer needs to store application configuration data that can be read by multiple EC2 instances. The data is less than 1 KB and changes frequently. Which AWS service is BEST suited for this?

Accepted Answer

AWS AppConfig. Option C is correct because AWS AppConfig is designed for application configuration and supports frequent updates. Option A is wrong because S3 is object storage, not ideal for small frequently changing configs. Option B is wrong because Parameter Store can store configs but is better for less frequent changes; AppConfig is optimized for frequent changes. Option D is wrong because DynamoDB is a database, overkill for simple config.

Answer

Amazon S3

Answer

AWS Systems Manager Parameter Store

Answer

Amazon DynamoDB

Question 9

A developer runs the above AWS CLI command to invoke a Lambda function. The response shows StatusCode 200 but FunctionError is 'Unhandled'. What does this indicate?

Accepted Answer

The function code threw an unhandled exception.. Option C is correct because 'Unhandled' means the Lambda function threw an exception that was not caught by the code. Option A is wrong because a timeout would result in a different error. Option B is wrong because a permission error would give a 403 status. Option D is wrong because the function was invoked but the error is in the code.

Answer

The function timed out.

Answer

The payload was malformed and the function did not run.

Answer

The function lacks execution permissions.

Question 10

A developer is using Amazon SQS to decouple microservices. The consumer service processes messages from the queue. To reduce processing time, the developer wants to receive multiple messages in a single API call. What is the maximum number of messages that can be received at once?

Accepted Answer

10. Option B is correct because the maximum number of messages that can be retrieved in a single ReceiveMessage call is 10. Option A is wrong because 5 is the default but not the max. Option C and D are wrong because they exceed the maximum.

Answer

5

Answer

100

Answer

20

Question 11

A developer needs to store a small amount of session state data (less than 1 MB) for a web application running on EC2. The data must be shared across multiple instances. Which solution is MOST cost-effective?

Accepted Answer

Use Amazon ElastiCache for session state.. Option A is correct because ElastiCache (Redis or Memcached) is designed for session state and is cost-effective. Option B is wrong because DynamoDB is more expensive for simple session state. Option C is wrong because S3 is slow for session state. Option D is wrong because EBS cannot be shared across instances.

Answer

Use an Amazon EBS volume with multi-attach.

Answer

Store session data in Amazon S3.

Answer

Use Amazon DynamoDB to store session data.

Question 12

A company has a Lambda function that writes to an S3 bucket. The IAM role used by the function has an inline policy allowing s3:PutObject on the bucket. However, writes fail with an access denied error. What is the MOST likely cause?

Accepted Answer

The S3 bucket has a bucket policy that denies the request.. Option D is correct because S3 bucket policies can explicitly deny access even if IAM allows it. Option A is wrong because the function role has permissions. Option B is wrong because S3 does not require VPC endpoints. Option C is wrong because KMS encryption requires additional permissions, but access denied could be due to bucket policy deny.

Answer

The S3 bucket is in a different region.

Answer

The S3 bucket uses SSE-KMS encryption and the function lacks kms:Decrypt permissions.

Answer

The Lambda function does not have the correct execution role.

Question 13

A developer is designing a system that ingests high-volume data from IoT devices. The data must be processed in near real-time and then stored in Amazon S3 for analytics. Which TWO AWS services should the developer use together to meet these requirements? (Choose TWO.)

Accepted Answer

Amazon Kinesis Data Streams. Options A and D are correct. Amazon Kinesis Data Streams can ingest high-volume streaming data, and AWS Lambda can process the stream in near real-time. Option B is wrong because SQS is for message queues, not streaming. Option C is wrong because SNS is for pub/sub, not streaming. Option E is wrong because EC2 is not serverless and requires management.

Answer

Amazon SQS

Answer

Amazon SNS

Answer

Amazon EC2

Question 14

A developer is creating a CI/CD pipeline for a serverless application using AWS CodePipeline. The application includes Lambda functions and an API Gateway REST API. The pipeline should automatically deploy changes when code is pushed to a Git repository. Which THREE actions are required to set this up? (Choose THREE.)

Accepted Answer

Use AWS CloudFormation with a template to deploy the infrastructure.. Options A, C, and E are correct. CodePipeline needs a source stage (CodeCommit), a build stage (CodeBuild), and a deploy stage (CloudFormation). Option B is wrong because CodeDeploy is for EC2/Lambda but CloudFormation is more appropriate for serverless resources. Option D is wrong because CodeStar is not required.

Answer

Use AWS CodeStar to create a project dashboard.

Answer

Use CodeDeploy to deploy the application to Lambda.

Question 15

A company is running a web application on EC2 instances behind an Application Load Balancer. The application experiences high latency during peak hours. A developer needs to improve performance. Which TWO actions should the developer take? (Choose TWO.)

Accepted Answer

Configure Auto Scaling to add more instances during peak hours.. Options A and C are correct. Auto Scaling adds instances during peak hours, spreading the load. ElastiCache caches database results, reducing latency. Option B is wrong because increasing instance size helps but is less elastic. Option D is wrong because increasing ALB idle timeout does not affect latency. Option E is wrong because EBS optimization is about network throughput, not application latency.

Answer

Increase the ALB idle timeout.

Answer

Use larger EC2 instance types.

Answer

Enable EBS optimization on the instances.