Free AWS Certified Developer - Associate (DVA-C02) Practice Questions

Sample DVA-C02 Practice Questions

Browse all 11 free AWS Certified Developer - Associate practice questions below.

1. The customer feedback functionality for a company's flagship web application is handled via an Amazon API Gateway based REST API that invokes an AWS Lambda function for further processing. Although the performance of the function is satisfactory, the development team has been tasked to optimize the startup time of the Lambda function to further improve the customer experience. How will you optimize the Lambda function for faster initialization?

   • Configure an interface VPC endpoint powered by AWS PrivateLink to access the Amazon API Gateway REST API with milliseconds latency
   • Configure provisioned concurrency for the Lambda function to respond immediately to the function's invocations
   • Enable API caching in Amazon API Gateway to cache AWS Lambda function response
   • Configure reserved concurrency to guarantee the maximum number of concurrent instances of the Lambda function

2. An EC2 instance has an IAM instance role attached to it, providing it read and write access to the S3 bucket 'my_bucket'. You have tested the IAM instance role and both reads and writes are working. You then remove the IAM role from the EC2 instance and test both read and write again. Writes stopped working but reads are still working. What is the likely cause of this behavior?

   • When a read is done on a bucket, there's a grace period of 5 minutes to do the same read again
   • The S3 bucket policy authorizes reads
   • The EC2 instance is using cached temporary IAM credentials
   • Removing an instance role from an EC2 instance can take a few minutes before being active

3. A financial services company has developed a REST API which is deployed in an Auto Scaling Group behind an Application Load Balancer. The API stores the data payload in DynamoDB and the static content is served through S3. Upon analyzing the usage pattern, it's found that 80% of the read requests are shared across all users. As a Developer Associate, how can you improve the application performance while optimizing the cost with the least development effort?

   • Enable DynamoDB Accelerator (DAX) for DynamoDB and CloudFront for S3
   • Enable ElastiCache Redis for DynamoDB and ElastiCache Memcached for S3
   • Enable DAX for DynamoDB and ElastiCache Memcached for S3
   • Enable ElastiCache Redis for DynamoDB and CloudFront for S3

4. A developer has defined a Lambda integration in Amazon API Gateway using a stage variable. However, when the developer invokes the API method, it consistently returns an "Internal server error" and a 500 status code. What steps should the developer take to fix the issue?

   • If you create a stage variable to call a function through your API, you must add the required permissions. Create an IAM role that your Lambda function can assume when invoking the respective AWS resources
   • API calls can't exceed the maximum allowed API request rate per account and per Region. Implement error retries and exponential backoffs to fix the error
   • If you create a stage variable to call a Lambda function through your API, you must add the required permissions. Update your Lambda function's resource-based AWS Identity and Access Management (IAM) policy so that it grants invoke permission to the API Gateway
   • When setting the Lambda function as the value of a stage variable, use the function's ARN and not the function alias for setting up the value

5. A company has a new media application that utilizes an Amazon CloudFront distribution that accesses the S3 bucket by using an origin access identity (OAI). The S3 bucket has an explicit access denial for all other users. A developer wants to allow access to the login page for unauthenticated users while ensuring the security of all private content that has restricted viewer access. Which of the following will you recommend?

   • Configure a new distribution having the same origin as the original distribution and set the path pattern for the default cache behavior of the new distribution as the path of the login page with viewer access as unrestricted. Keep the default cache behavior of the original distribution unchanged
   • Configure a second cache behavior to the distribution having the same origin as the default cache behavior and have the path pattern for the second cache behavior as * with viewer access as restricted. Modify the default cache behavior's path pattern to the path of the login page and have the viewer access as unrestricted
   • Configure a second origin as the failover origin for the default behavior of the original distribution and have the path pattern for the second origin as the path of the login page with viewer access as unrestricted. Keep the behavior for the primary origin unchanged
   • Configure a second cache behavior to the distribution having the same origin as the default cache behavior and have the path pattern for the second cache behavior as the path of the login page with viewer access as unrestricted. Keep the default cache behavior's settings unchanged

6. A development team is building a Java-based serverless application using AWS Lambda. The application experiences variable cold start latency of several seconds, which is impacting user experience. The team wants to reduce the startup time to sub-second performance with minimal code changes. Which solution will provide the best cold start optimization for this Java Lambda function?

   • Enable Lambda SnapStart for the Java function
   • Configure provisioned concurrency for the Lambda function
   • Increase the Lambda function's memory allocation to 3008 MB
   • Use CloudWatch Events to invoke the Lambda function every 5 minutes to keep it warm

7. A developer is building a serverless application that processes uploaded images. Users upload images to an S3 bucket, which triggers a Lambda function to create thumbnails. The Lambda function sometimes fails due to timeout when processing very large images. What is the BEST approach to handle this scenario?

   • Implement an asynchronous processing pattern using SQS queue and increase Lambda timeout to maximum (15 minutes)
   • Increase Lambda memory allocation to provide more CPU power for faster processing
   • Configure S3 to reject uploads of images larger than a specific size
   • Split the Lambda function into multiple smaller functions that process the image in parallel

8. A developer is building a Lambda function that processes large JSON files from S3 (up to 500MB). The function runs out of memory when trying to parse the entire file. What is the BEST approach to handle this scenario?

   • Use streaming to read and process the S3 file in chunks instead of loading the entire file into memory
   • Increase the Lambda function's memory allocation to 10GB (maximum) to accommodate the large files
   • Split the S3 file into smaller chunks using a separate Lambda function before processing
   • Download the S3 file to Lambda's /tmp directory and process it using memory-mapped file I/O

9. A development team is building a REST API with API Gateway and Lambda. Some endpoints require complex authorization logic based on user attributes, resource ownership, and time-based access. Which authorization approach should they use?

   • Implement a Lambda authorizer (custom authorizer) with caching enabled
   • Use Cognito User Pool authorizer and implement authorization logic in each Lambda function
   • Use IAM authorization and attach policies to each user
   • Use API Gateway resource policies to control access to specific endpoints

10. A Lambda function processes IoT sensor data and stores it in DynamoDB. The function receives batches of sensor readings and must ensure that all records are written to DynamoDB atomically - either all succeed or all fail. What DynamoDB feature should be used?

    • Use DynamoDB TransactWriteItems API to write all records in a single transaction
    • Use DynamoDB BatchWriteItem API and implement custom rollback logic in Lambda if any write fails
    • Enable DynamoDB Streams and use a Lambda function to validate that all records were written successfully
    • Use DynamoDB Conditional Writes with a consistent version number across all items

11. A serverless application uses Lambda functions that process messages from an SQS queue. During high traffic periods, some messages fail processing and are returned to the queue repeatedly, causing the same messages to be processed multiple times without success. How should the developer prevent problematic messages from blocking the queue?

    • Configure a Dead Letter Queue (DLQ) on the SQS queue with a maxReceiveCount threshold
    • Increase the SQS visibility timeout to give Lambda more time to process messages
    • Implement error handling in Lambda to catch exceptions and delete failed messages from the queue
    • Enable SQS long polling to reduce the number of empty receives and improve processing efficiency