aws developer associate practice exam Practice Exam 2025: Latest Questions

A developer is storing user-uploaded images in an Amazon S3 bucket. The application must allow users to upload directly from a browser without exposing AWS credentials. Which solution should the developer use?

A Lambda function processes messages from an Amazon SQS queue. Occasionally, the same message is processed more than once. The developer wants the application to behave correctly even with duplicate deliveries. What should the developer do?

A developer needs to securely store and regularly rotate a database password used by an application running on Amazon ECS. Which AWS service is the BEST fit for storing the secret and enabling rotation?

A developer is deploying a new version of a Lambda function. They want to route 10% of traffic to the new version for a canary test and then gradually shift more traffic if no errors occur. Which Lambda feature should they use?

An application uses Amazon API Gateway with a Lambda integration. The Lambda function is timing out, and the developer needs to determine whether the delay is in API Gateway or in downstream calls made by the Lambda function. Which approach provides the MOST actionable tracing across services?

A developer is building a serverless workflow using AWS Step Functions. One task calls an external payment API that sometimes fails with transient errors. The workflow should retry with exponential backoff and stop after a fixed number of attempts. What is the BEST way to implement this behavior?

A developer deploys an application to Amazon ECS on AWS Fargate. Tasks must call AWS services (for example, S3 and DynamoDB) without embedding credentials in the container image. Which solution should the developer use?

A developer is using AWS CodeDeploy to deploy to Amazon EC2 instances in an Auto Scaling group. The developer wants to run validation tests on each instance before allowing traffic to it, and automatically roll back if the validation fails. Which CodeDeploy feature BEST meets this requirement?

A Lambda function reads items from a DynamoDB table and returns them through API Gateway. Under load, the function frequently throttles when calling DynamoDB. The developer has confirmed the table has sufficient provisioned capacity (or on-demand scaling) for the workload. What is the MOST likely cause and best fix?

A company wants to run integration tests against a production-like environment whenever code is merged. The pipeline must deploy the same application version to a temporary environment, run tests, and then automatically tear the environment down. The team wants minimal infrastructure management and reproducible environments. Which solution is BEST?

A Lambda function reads an item from DynamoDB, increments a counter, and writes it back. Under load, the counter occasionally decreases or repeats values. Which change will MOST effectively prevent lost updates?

A developer needs to call an Amazon API Gateway REST API from a web browser application hosted on a different domain. The browser blocks the call due to missing CORS headers. What should the developer do to fix this?

A developer wants an ECS task to read objects from a specific S3 bucket without storing long-term AWS access keys. The ECS task runs on AWS Fargate. Which approach follows AWS best practices?

A Lambda function is triggered by an SQS queue. Messages are sometimes processed more than once, causing duplicate records in a downstream system. Which design change is MOST appropriate to handle this behavior?

A CI/CD pipeline deploys a new Lambda version using an alias named "prod". The team wants to gradually shift 10% of traffic to the new version and automatically roll back if errors increase. Which approach meets these requirements with the LEAST operational effort?

An application running on Amazon EC2 in a private subnet needs to retrieve a database password stored in AWS Secrets Manager. The instance has no internet access. Which solution allows retrieval without exposing Secrets Manager to the public internet?

A developer is troubleshooting an API Gateway + Lambda integration that intermittently returns HTTP 502. CloudWatch logs show "Task timed out after X seconds" for the Lambda function. What is the MOST likely cause?

A Lambda function in Account A must publish messages to an SNS topic in Account B. The developer wants to use least privilege and avoid long-term credentials. Which solution is MOST appropriate?

A containerized application on Amazon ECS uses AWS SDK calls to DynamoDB. Occasionally, requests fail with throttling errors during traffic spikes. The developer wants to minimize retries and reduce throttling without changing application code significantly. Which solution is BEST?

A company uses AWS CloudFormation to deploy an application stack. A failed update left the stack in UPDATE_ROLLBACK_FAILED. The developer needs to continue managing the stack with minimal disruption and preserve existing resources where possible. What should the developer do FIRST?

A developer is building an AWS Lambda function that processes orders. The function needs access to a third-party API key. The key must be encrypted at rest, rotated without code changes, and only the Lambda function should be able to retrieve it. Which solution meets these requirements with the LEAST operational effort?

A team uses Amazon API Gateway (REST API) with AWS Lambda proxy integration. The backend Lambda function returns HTTP 200 responses, but clients intermittently receive 502 Bad Gateway from API Gateway. CloudWatch logs for the Lambda function show occasional timeouts when calling a downstream service. What is the MOST likely cause of the 502 errors?

A developer is deploying a new version of a Lambda function used by a production application. The developer must shift traffic gradually to the new version and automatically roll back if the new version increases errors. Which approach is MOST appropriate?

A serverless application uses Amazon DynamoDB to store items. A new access pattern requires querying items by a non-key attribute. The application must support this query efficiently without scanning the table. Which solution should the developer implement?

An application deployed on Amazon ECS (Fargate) pulls sensitive configuration values at startup from AWS Systems Manager Parameter Store (SecureString). Tasks intermittently fail to start with AccessDenied errors for kms:Decrypt even though the task role has ssm:GetParameter permission. What should the developer do to fix the issue?