Amazon DVA-C01 Online Practice Questions and Exam Preparation

Amazon DVA-C01 Online Questions & Answers

• Question 421:

  A Developer is receiving HTTP 400: ThrottlingException errors intermittently when calling the Amazon CloudWatch API. When a call fails, no data is retrieved.

  What best practice should first be applied to address this issue?

  A. Contact AWS Support for a limit increase.

  B. Use the AWS CLI to get the metrics

  C. Analyze the applications and remove the API call

  D. Retry the call with exponential backoff

  Correct Answer: D

  https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/cloudwatch_limits.html

• Question 422:

  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?

  A. AWS Data Pipeline

  B. AWS SNS with AWS SQS

  C. Amazon Elastic MapReduce

  D. AWS Step Functions

  Correct Answer: D

  https://aws.amazon.com/step-functions/

• Question 423:

  A startup s photo-sharing site is deployed in a VPC. An ELB distributes web traffic across two subnets. ELB session stickiness is configured to use the AWS-generated session cookie, with a session TTL of 5 minutes. The webserver Auto

  Scaling Group is configured as: min-size=4, max-size=4.

  The startups preparing for a public launch, by running load-testing software installed on a single EC2 instance running in us-west-2a. After 60 minutes of load-testing, the webserver logs show:

  Which recommendations can help ensure load-testing HTTP requests are evenly distributed across the four webservers? Choose 2 answers

  A. Launch and run the load-tester EC2 instance from us-east-1 instead.

  B. Re-configure the load-testing software to re-resolve DNS for each web request.

  C. Use a 3rd-party load-testing service which offers globally-distributed test clients.

  D. Configure ELB and Auto Scaling to distribute across us-west-2a and us-west-2c.

  E. Configure ELB session stickiness to use the app-specific session cookie.

  Correct Answer: CE

• Question 424:

  What does an Amazon SQS delay queue accomplish?

  A. Messages are hidden for a configurable amount of time when they are first added to the queue.

  B. Messages are hidden for a configurable amount of time after they are consumed from the queue.

  C. The consumer can poll the queue for a configurable amount of time before retrieving a message.

  D. Message cannot be deleted for a configurable amount of time after they are consumed from the queue.

  Correct Answer: A

  Reference:

  https://docs.aws.amazon.com/AWSSimpleQueueService/latest/SQSDeveloperGuide/sqs- delayqueues.html

• Question 425:

  An application is running on a cluster of Amazon EC2 instances. While trying to read objects stored within a single Amazon S3 bucket that are encrypted with server-side encryption with AWS KMS managed keys (SSE-KMS), the application receives the following error:

  

  Which combination of steps should be taken to prevent this failure? (Choose two.)

  A. Contact AWS Support to request an AWS KMS rate limit increase.

  B. Perform error retries with exponential backoff in the application code.

  C. Contact AWS Support to request a S3 rate limit increase.

  D. Import a customer master key (CMK) with a larger key size.

  E. Use more than one customer master key (CMK) to encrypt S3 data

  Correct Answer: AD

• Question 426:

  AWS CodeBuild builds code for an application, creates the Docker image, pushes the image to Amazon Elastic Container Registry (Amazon ECR), and tags the image with a unique identifier. If the Developers already have AWS CLI configured on their workstations, how can the Docker images be pulled to the workstations?

  A. Run the following:docker pull REPOSITORY URI : TAG

  B. Run the output of the following:aws ecr get-loginand then run:docker pull REPOSITORY URI : TAG

  C. Run the following:aws ecr get-loginand then run:docker pull REPOSITORY URI : TAG

  D. Run the output of the following:aws ecr get-download-url-for-layerand then run:docker pull REPOSITORY URI : TAG

  Correct Answer: B

  https://docs.aws.amazon.com/cli/latest/reference/ecr/get-login.html

• Question 427:

  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?

  A. Use the ChangeMessageVisibility API to increase the VisibilityTimeout, then use the DeleteMessage API to delete the message.

  B. Use the DeleteMessage API call to delete the message from the queue, then call DeleteQueue API to remove the queue.

  C. Use the ChangeMessageVisibility API to decrease the timeout value, then use the DeleteMessage API to delete the message.

  D. Use the DeleteMessageVisibility API to cancel the VisibilityTimeout, then use the DeleteMessage API to delete the message.

  Correct Answer: A

  https://docs.aws.amazon.com/AWSSimpleQueueService/latest/SQSDeveloperGuide/sqs-visibility- timeout.html In SQS, messages remain there. It is the consumer's responsibility to delete it, once consumed and processed.

• Question 428:

  A Developer is writing an imaging micro service on AWS Lambda. The service is dependent on several libraries that are not available in the Lambda runtime environment. Which strategy should the Developer follow to create the Lambda deployment package?

  A. Create a ZIP file with the source code and all dependent libraries.

  B. Create a ZIP file with the source code and a script that installs the dependent libraries at runtime.

  C. Create a ZIP file with the source code. Stage the dependent libraries on an Amazon S3 bucket indicated by the Lambda environment variable LD_LIBRARY_PATH

  D. Create a ZIP file with the source code and a buildspec.yaml file that installs the dependent libraries on AWS Lambda.

  Correct Answer: B

• Question 429:

  A deployment package uses the AWS CLI to copy files into any S3 bucket in the account, using access keys stored in environment variables. The package is running on EC2 instances, and the instances have been modified to run with an

  assumed IAM role and a more restrictive policy that allows access to only one bucket.

  After the change, the Developer logs into the host and still has the ability to write into all of the S3 buckets in that account.

  What is the MOST likely cause of this situation?

  A. An IAM inline policy is being used on the IAM role

  B. An IAM managed policy is being used on the IAM role

  C. The AWS CLI is corrupt and needs to be reinstalled

  D. The AWS credential provider looks for instance profile credentials last

  Correct Answer: B

  https://docs.aws.amazon.com/sdk-for-java/v1/developer-guide/credentials.html

• Question 430:

  An AWS Lambda function generates a 3MB JSON file and then uploads it to an Amazon S3 bucket daily. The file contains sensitive information, so the Developer must ensure that it is encrypted before uploading to the bucket. Which of the following modifications should the Developer make to ensure that the data is encrypted before uploading it to the bucket?

  A. Use the default AWS KMS customer master key for S3 in the Lambda function code.

  B. Use the S3 managed key and call the GenerateDataKey API to encrypt the file.

  C. Use the GenerateDateKey API, then use that data key to encrypt the file in the Lambda function code.

  D. Use a custom KMS customer master key created for S3 in the Lambda function code.

  Correct Answer: C