Free Practice Questions for Amazon DVA-C02 Exam

A company is using an AWS Lambda function to process records from an Amazon Kinesis data stream. The company recently observed slow processing of the records. A developer notices that the iterator age metric for the function is increasing and that the Lambda run duration is constantly above normal.Which actions should the developer take to increase the processing speed? (Choose two.)

• Increase the number of shards of the Kinesis data stream.
• Decrease the timeout of the Lambda function.
• Increase the memory that is allocated to the Lambda function.
• Decrease the number of shards of the Kinesis data stream.
• Increase the timeout of the Lambda function.

A developer has an application that makes batch requests directly to Amazon DynamoDB by using the BatchGetItem low-level API operation. The responses frequently return values in the UnprocessedKeys element.Which actions should the developer take to increase the resiliency of the application when the batch response includes values in UnprocessedKeys? (Choose two.)

• Retry the batch operation immediately.
• Retry the batch operation with exponential backoff and randomized delay.
• Update the application to use an AWS software development kit (AWS SDK) to make the requests.
• Increase the provisioned read capacity of the DynamoDB tables that the operation accesses.
• Increase the provisioned write capacity of the DynamoDB tables that the operation accesses.

A developer has created an AWS Lambda function that is written in Python. The Lambda function reads data from objects in Amazon S3 and writes data to an Amazon DynamoDB table. The function is successfully invoked from an S3 event notification when an object is created. However, the function fails when it attempts to write to the DynamoDB table.What is the MOST likely cause of this issue?

• The Lambda function's concurrency limit has been exceeded.
• DynamoDB table requires a global secondary index (GSI) to support writes.
• The Lambda function does not have IAM permissions to write to DynamoDB.
• The DynamoDB table is not running in the same Availability Zone as the Lambda function.

A developer is creating an application that will store personal health information (PHI). The PHI needs to be encrypted at all times. An encrypted Amazon RDS for MySQL DB instance is storing the data. The developer wants to increase the performance of the application by caching frequentlyaccessed data while adding the ability to sort or rank the cached datasets. Which solution will meet these requirements?

• Create an Amazon ElastiCache for Redis instance. Enable encryption of data in transit and at rest. Store frequently accessed data in the cache.
• Create an Amazon ElastiCache for Memcached instance. Enable encryption of data in transit and at rest. Store frequently accessed data in the cache.
• Create an Amazon RDS for MySQL read replica. Connect to the read replica by using SSL. Configure the read replica to store frequently accessed data.
• Create an Amazon DynamoDB table and a DynamoDB Accelerator (DAX) cluster for the table. Store frequently accessed data in the DynamoDB table.

An application uses an Amazon EC2 Auto Scaling group. A developer notices that EC2 instances are taking a long time to become available during scale-out events. The UserData script is taking a long time to run.The developer must implement a solution to decrease the time that elapses before an EC2 instance becomes available. The solution must make the most recent version of the application available at all times and must apply all available security updates. The solution also must minimize the number of images that are created. The images must be validated.Which combination of steps should the developer take to meet these requirements? (Choose two.)

• Use EC2 Image Builder to create an Amazon Machine Image (AMI). Install all the patches and agents that are needed to manage and run the application. Update the Auto Scaling group launch configuration to use the AMI.
• Use EC2 Image Builder to create an Amazon Machine Image (AMI). Install the latest version of the application and all the patches and agents that are needed to manage and run the application. Update the Auto Scaling group launch configuration to use the AMI.
• Set up AWS CodeDeploy to deploy the most recent version of the application at runtime.
• Set up AWS CodePipeline to deploy the most recent version of the application at runtime.
• Remove any commands that perform operating system patching from the UserData script.

A developer is creating a mobile app that calls a backend service by using an Amazon API Gateway REST API. For integration testing during the development phase, the developer wants to simulate different backend responses without invoking the backend service.Which solution will meet these requirements with the LEAST operational overhead?

• Create an AWS Lambda function. Use API Gateway proxy integration to return constant HTTP responses.
• Create an Amazon EC2 instance that serves the backend REST API by using an AWSCloudFormation template.
• Customize the API Gateway stage to select a response type based on the request.
• Use a request mapping template to select the mock integration response.

A developer is using an AWS Lambda function to generate avatars for profile pictures that are uploaded to an Amazon S3 bucket. The Lambda function is automatically invoked for profile pictures that are saved under the /original/ S3 prefix. The developer notices that some pictures cause the Lambda function to time out. The developer wants to implement a fallback mechanism by using another Lambda function that resizes the profile picture.Which solution will meet these requirements with the LEAST development effort?

• Set the image resize Lambda function as a destination of the avatar generator Lambda function for the events that fail processing.
• Create an Amazon Simple Queue Service (Amazon SQS) queue. Set the SQS queue as a destination with an on failure condition for the avatar generator Lambda function. Configure the image resize Lambda function to poll from the SQS queue.
• Create an AWS Step Functions state machine that invokes the avatar generator Lambda function and uses the image resize Lambda function as a fallback. Create an Amazon EventBridge rule that matches events from the S3 bucket to invoke the state machine.
• Create an Amazon Simple Notification Service (Amazon SNS) topic. Set the SNS topic as a destination with an on failure condition for the avatar generator Lambda function. Subscribe the image resize Lambda function to the SNS topic.

An application is using Amazon Cognito user pools and identity pools for secure access. A developer wants to integrate the user-specific file upload and download features in the application with Amazon S3. The developer must ensure that the files are saved and retrieved in a secure manner and that users can access only their own files. The file sizes range from 3 KB to 300 MB.Which option will meet these requirements with the HIGHEST level of security?

• Use S3 Event Notifications to validate the file upload and download requests and update the user interface (UI).
• Save the details of the uploaded files in a separate Amazon DynamoDB table. Filter the list of files in the user interface (UI) by comparing the current user ID with the user ID associated with the file in the table.
• Use Amazon API Gateway and an AWS Lambda function to upload and download files. Validate each request in the Lambda function before performing the requested operation.
• Use an IAM policy within the Amazon Cognito identity prefix to restrict users to use their own folders in Amazon S3.

A developer is building a new application on AWS. The application uses an AWS Lambda function that retrieves information from an Amazon DynamoDB table. The developer hard coded the DynamoDB table name into the Lambda function code. The table name might change over time. The developer does not want to modify the Lambda code if the table name changes.Which solution will meet these requirements MOST efficiently?

• Create a Lambda environment variable to store the table name. Use the standard method for the programming language to retrieve the variable.
• Store the table name in a file. Store the file in the /tmp folder. Use the SDK for the programming language to retrieve the table name.
• Create a file to store the table name. Zip the file and upload the file to the Lambda layer. Use the SDK for the programming language to retrieve the table name.
• Create a global variable that is outside the handler in the Lambda function to store the table name.

A developer is creating an application that will be deployed on IoT devices. The application will send data to a RESTful API that is deployed as an AWS Lambda function. The application will assign each API request a unique identifier. The volume of API requests from the application can randomly increase at any given time of day.During periods of request throttling, the application might need to retry requests. The API must be able to handle duplicate requests without inconsistencies or data loss.Which solution will meet these requirements?

• Create an Amazon RDS for MySQL DB instance. Store the unique identifier for each request in adatabase table. Modify the Lambda function to check the table for the identifier before processing the request.
• Create an Amazon DynamoDB table. Store the unique identifier for each request in the table. Modify the Lambda function to check the table for the identifier before processing the request.
• Create an Amazon DynamoDB table. Store the unique identifier for each request in the table. Modify the Lambda function to return a client error response when the function receives a duplicate request.
• Create an Amazon ElastiCache for Memcached instance. Store the unique identifier for each request in the cache. Modify the Lambda function to check the cache for the identifier before processing the request.