AWS Certified Developer–Associate DVA-C01 Real Questions

1. A Developer created a dashboard for an application using Amazon API Gateway, Amazon S3, AWS Lambda, and Amazon RDS. The Developer needs an authentication mechanism allowing a user to sign in and view the dashboard. It must be accessible from mobile applications, desktops, and tablets, and must remember user preferences across platforms.

Which AWS service should the Developer use to support this authentication scenario?

2. A Developer has created an S3 bucket s3://mycoolappand has enabled server across logging that points to the folder s3://mycoolapp/logs.The Developer moved 100 KB of Cascading Style Sheets (CSS) documents to the folder s3://mycoolapp/css, and then stopped work. When the developer came back a few days later, the bucket was 50 GB.

What is the MOST likely cause of this situation?

3. A Developer is creating an Auto Scaling group whose instances need to publish a custom metric to Amazon CloudWatch.

Which method would be the MOST secure way to authenticate a CloudWatch PUT request?

4. A Developer is working on an application that tracks hundreds of millions of product reviews in an Amazon DynamoDB table.

The records include the data elements shown in the table:

Which field, when used as the partition key, would result in the MOST consistent performance using DynamoDB?

5. A Developer has written a serverless application using multiple AWS services. The business logic is written as a Lambda function which has dependencies on third-party libraries. The Lambda function endpoints will be exposed using Amazon API Gateway. The Lambda function will write the information to Amazon DynamoDB. The Developer is ready to deploy the application but must have the ability to rollback.

How can this deployment be automated, based on these requirements?

6. What are the steps to using the AWS CLI to launch a templatized serverless application?

7. A Developer is creating a web application that requires authentication, but also needs to support guest access to provide users limited access without having to authenticate.

What service can provide support for the application to allow guest access?

8. An application takes 40 seconds to process instructions received in an Amazon SQS message.

Assuming the SQS queue is configured with the default VisibilityTimeout value, what is the BEST way, upon receiving a message, to ensure that no other instances can retrieve a message that has already been processed or is currently being processed?

9. A Developer has implemented a Lambda function that needs to add new customers to an RDS database that is expected to run hundreds of times per hour.

The Lambda function is configured to use 512MB of RAM and is based on the following pseudo code:

After testing the Lambda function, the Developer notices that the Lambda execution time is much longer than expected.

What should the Developer do to improve performance?

10. A current architecture uses many Lambda functions invoking one another as a large state machine. The coordination of this state machine is legacy custom code that breaks easily.

Which AWS Service can help refactor and manage the state machine?

11. A Developer is asked to implement a caching layer in front of Amazon RDS. Cached content is expensive to regenerate in case of service failure.

Which implementation below would work while maintaining maximum uptime?

12. A current architecture uses many Lambda functions invoking one another as large state machine. The coordination of this state machine is legacy custom code that breaks easily.

Which AWS Service can help refactor and manage the state machine?

13. A large e-commerce site is being designed to deliver static objects from Amazon S3. The Amazon S3 bucket will server more than 300 GET requests per second.

What should be done to optimize performance? (Choose two.)

14. A company is building a stock trading application that requires sub-millisecond latency in processing trading requests. Amazon DynamoDB is used to store all the trading data that is used to process each request. After load testing the application, the development team found that due to data retrieval times, the latency requirement is not satisfied. Because of sudden high spikes in the number of requests, DynamoDB read capacity has to be significantly over-provisioned to avoid throttling.

What steps should be taken to meet latency requirements and reduce the cost of running the application?

15. A Developer needs temporary access to resources in a second account.

What is the MOST secure way to achieve this?

16. An application reads data from an Amazon DynamoDB table. Several times a day, for a period of 15 seconds, the application receives multiple ProvisionedThroughputExceeded errors.

How should this exception be handled?

17. A Developer has created a large Lambda function, and deployment is failing with the following error:

ClientError: An error occurred (InvalidParameterValueException) when callingthe CreateFunction operation: Unzipped size must be smaller than XXXXXXXXX bytes’, where XXXXXXXXX is the current Lambda limit

What can the Developer do to fix this problem?

18. Given the source code for an AWS Lambda function in the local store.py containing a handler function called get_store and the following AWS CloudFormation template:

What should be done to prepare the template so that it can be deployed using the AWS CLI command aws cloudformation deploy?

19. An application stores images in an S3 bucket. Amazon S3 event notifications are used to trigger a Lambda function that resizes the images. Processing each image takes less than a second.

How will AWS Lambda handle the additional traffic?

20. A company wants to implement a continuous integration for its workloads on AWS. The company wants to trigger unit test in its pipeline for commits-on its code repository, and wants to be notified of failure events in the pipeline.

How can these requirements be met?