Amazon DVA-C02 Exam Practice Test Instant Access

Question 1

A developer is designing a fault-tolerant environment where client sessions will be saved.

How can the developer ensure that no sessions are lost if an Amazon EC2 instance fails?

AUse sticky sessions with an Elastic Load Balancer target group.

BUse Amazon SOS to save session data.

CUse Amazon DynamoDB to perform scalable session handling.

DUse Elastic Load Balancer connection draining to stop sending requests to failing instances.

Answer : C

Question 2

An ecommerce company is planning to migrate an on-premises Microsoft SQL Server database to the AWS Cloud. The company needs to migrate the database to SQL Server Always On availability groups. The cloud-based solution must be highly available.

Which solution will meet these requirements?

ADeploy three Amazon EC2 instances with SQL Server across three Availability Zones. Attach one Amazon Elastic Block Store (Amazon EBS) volume to the EC2 instances.

BMigrate the database to Amazon RDS for SQL Server. Configure a Multi-AZ deployment and read replicas.

CDeploy three Amazon EC2 instances with SQL Server across three Availability Zones. Use Amazon FSx for Windows File Server as the storage tier.

DDeploy three Amazon EC2 instances with SQL Server across three Availability Zones. Use Amazon S3 as the storage tier.

Answer : C

Why Option C is Correct:

SQL Server Always On availability groups require a shared storage solution. Amazon FSx for Windows File Server provides the shared storage necessary to implement Always On availability groups in a highly available configuration.

Why Other Options are Incorrect:

Option A: A single EBS volume cannot provide shared storage for Always On availability groups.

Option B: RDS does not support SQL Server Always On availability groups.

Option D: S3 is not a suitable storage tier for SQL Server database operations.

AWS Documentation Reference:

Amazon FSx for Windows File Server

Question 3

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.)

ARetry the batch operation immediately.

BRetry the batch operation with exponential backoff and randomized delay.

CUpdate the application to use an AWS software development kit (AWS SDK) to make the requests.

DIncrease the provisioned read capacity of the DynamoDB tables that the operation accesses.

EIncrease the provisioned write capacity of the DynamoDB tables that the operation accesses.

Answer : B, C

The UnprocessedKeys element indicates that the BatchGetItem operation did not process all of the requested items in the current response. This can happen if the response size limit is exceeded or if the table's provisioned throughput is exceeded. To handle this situation, the developer should retry the batch operation with exponential backoff and randomized delay to avoid throttling errors and reduce the load on the table. The developer should also use an AWS SDK to make the requests, as the SDKs automatically retry requests that return UnprocessedKeys.

[BatchGetItem - Amazon DynamoDB]

[Working with Queries and Scans - Amazon DynamoDB]

[Best Practices for Handling DynamoDB Throttling Errors]

Question 4

Users are reporting errors in an application. The application consists of several micro services that are deployed on Amazon Elastic Container Serves (Amazon ECS) with AWS Fargate.

When combination of steps should a developer take to fix the errors? (Select TWO)

ADeploy AWS X-Ray as a sidecar container to the micro services. Update the task role policy to allow access to me X -Ray API.

BDeploy AWS X-Ray as a daemon set to the Fargate cluster. Update the service role policy to allow access to the X-Ray API.

CInstrument the application by using the AWS X-Ray SDK. Update the application to use the Put-XrayTrace API call to communicate with the X-Ray API.

DInstrument the application by using the AWS X-Ray SDK. Update the application to communicate with the X-Ray daemon.

EInstrument the ECS task to send the stout and spider- output to Amazon CloudWatch Logs. Update the task role policy to allow the cloudwatch Putlogs action.

Answer : A, E

The combination of steps that the developer should take to fix the errors is to deploy AWS X-Ray as a sidecar container to the microservices and instrument the ECS task to send the stdout and stderr output to Amazon CloudWatch Logs. This way, the developer can use AWS X-Ray to analyze and debug the performance of the microservices and identify any issues or bottlenecks. The developer can also use CloudWatch Logs to monitor and troubleshoot the logs from the ECS task and detect any errors or exceptions. The other options either involve using AWS X-Ray as a daemon set, which is not supported by Fargate, or using the PutTraceSegments API call, which is not necessary when using a sidecar container.

Question 5

An application is processing clickstream data using Amazon Kinesis. The clickstream data feed into Kinesis experiences periodic spikes. The PutRecords API call occasionally fails and the logs show that the failed call returns the response shown below:

Which techniques will help mitigate this exception? (Choose two.)

AImplement retries with exponential backoff.

BUse a PutRecord API instead of PutRecords.

CReduce the frequency and/or size of the requests.

DUse Amazon SNS instead of Kinesis.

EReduce the number of KCL consumers.

Answer : A, C

The response from the API call indicates that the ProvisionedThroughputExceededException exception has occurred. This exception means that the rate of incoming requests exceeds the throughput limit for one or more shards in a stream. To mitigate this exception, the developer can use one or more of the following techniques:

Implement retries with exponential backoff. This will introduce randomness in the retry intervals and avoid overwhelming the shards with retries.

Reduce the frequency and/or size of the requests. This will reduce the load on the shards and avoid throttling errors.

Increase the number of shards in the stream. This will increase the throughput capacity of the stream and accommodate higher request rates.

Use a PutRecord API instead of PutRecords. This will reduce the number of records per request and avoid exceeding the payload limit.

[ProvisionedThroughputExceededException - Amazon Kinesis Data Streams Service API Reference]

[Best Practices for Handling Kinesis Data Streams Errors]

Question 6

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?

ACreate an AWS Lambda function. Use API Gateway proxy integration to return constant HTTP responses.

BCreate an Amazon EC2 instance that serves the backend REST API by using an AWS CloudFormation template.

CCustomize the API Gateway stage to select a response type based on the request.

DUse a request mapping template to select the mock integration response.

Answer : D

Amazon API Gateway supports mock integration responses, which are predefined responses that can be returned without sending requests to a backend service. Mock integration responses can be used for testing or prototyping purposes, or for simulating different backend responses based on certain conditions. A request mapping template can be used to select a mock integration response based on an expression that evaluates some aspects of the request, such as headers, query strings, or body content. This solution does not require any additional resources or code changes and has the least operational overhead. Reference:Set up mock integrations for an API Gateway REST API

https://docs.aws.amazon.com/apigateway/latest/developerguide/how-to-mock-integration.html

Question 7

A team of developed is using an AWS CodePipeline pipeline as a continuous integration and continuous delivery (CI/CD) mechanism for a web application. A developer has written unit tests to programmatically test the functionality of the application code. The unit tests produce a test report that shows the results of each individual check. The developer now wants to run these tests automatically during the CI/CD process.

AWrite a Git pre-commit hook that runs the test before every commit. Ensure that each developer who is working on the project has the pre-commit hook instated locally. Review the test report and resolve any issues before pushing changes to AWS CodeCommit.

BAdd a new stage to the pipeline. Use AWS CodeBuild as the provider. Add the new stage after the stage that deploys code revisions to the test environment. Write a buildspec that fails the CodeBuild stage if any test does not pass. Use the test reports feature of Codebuild to integrate the report with the CodoBuild console. View the test results in CodeBuild Resolve any issues.

CAdd a new stage to the pipeline. Use AWS CodeBuild at the provider. Add the new stage before the stage that deploys code revisions to the test environment. Write a buildspec that fails the CodeBuild stage it any test does not pass. Use the test reports feature of CodeBuild to integrate the report with the CodeBuild console. View the test results in codeBuild Resolve any issues.

DAdd a new stage to the pipeline. Use Jenkins as the provider. Configure CodePipeline to use Jenkins to run the unit tests. Write a Jenkinsfile that fails the stage if any test does not pass. Use the test report plugin for Jenkins to integrate the repot with the Jenkins dashboard. View the test results in Jenkins. Resolve any issues.

Answer : C

The solution that will meet the requirements is to add a new stage to the pipeline. Use AWS CodeBuild as the provider. Add the new stage before the stage that deploys code revisions to the test environment. Write a buildspec that fails the CodeBuild stage if any test does not pass. Use the test reports feature of CodeBuild to integrate the report with the CodeBuild console. View the test results in CodeBuild. Resolve any issues. This way, the developer can run the unit tests automatically during the CI/CD process and catch any bugs before deploying to the test environment. The developer can also use the test reports feature of CodeBuild to view and analyze the test results in a graphical interface. The other options either involve running the tests manually, running them after deployment, or using a different provider that requires additional configuration and integration.

Amazon AWS Certified Developer - Associate DVA-C02 Exam Practice Test