AWS-Certified-Developer-Associate Free Practice Test

- (Exam Topic 4)
An ecommerce application is running behind an Application Load Balancer. A developer observes some unexpected load on the application during non-peak hours. The developer wants to analyze patterns for the client IP addresses that use the application.
Which HTTP header should the developer use for this analysis?

1. A. The X-Forwarded-Proto header
2. B. The X-Forwarded-Host header
3. C. The X-Forwarded-For header
4. D. The X-Forwarded-Port header

Correct Answer: C
https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Forwarded-Proto

- (Exam Topic 2)
A company has a legacy application that was migrated to a fleet of Amazon EC2 instances. The application stores data in a MySQL database that is currently installed on a single EC2 instance The company has decided to migrate the database from the EC2 instance to MySQL on Amazon RDS.
What should the developer do to update the application to support data storage in Amazon RDS?

1. A. Update the database connection parameters in the application to point to the new RDS instance
2. B. Add a script to the EC2 instance that implements an AWS SDK for requesting database credentials.
3. C. Create a new EC2 instance with an IAM role that allows access to the new RDS database
4. D. Create an AWS Lambda function that will route traffic from the EC2 instance to the RDS database.

Correct Answer: A

- (Exam Topic 4)
A developer at a company recently created a serverless application to process and show data from business reports. The application's user interface (Ul) allow users to select and start processing the files. The Ul displays a message when the result is available to view. The application uses AWS Step Functions with A Lambda functions "to process the files. The developer used Amazon API Gateway and Lambda functions to create an API to support the Ul.
The company's Ul team reports that the request to process a file is often returning timeout errors because of the size or complexity of the files. The Ul team w< API>What should the developer do to configure the API to meet these requirements?

1. A. Change the API Gateway route to add an X-Amz-lnvocation-Type header with a static value of 'Event' in the integration reques
2. B. Deploy the API Gatt stage to apply the changes.
3. C. Change the configuration of the Lambda function that implements the request to process a file.Configure the maximum age of the event so that the Lambda function will run asynchronously.
4. D. Change the API Gateway timeout value to match the Lambda function timeout valu
5. E. Deploy the API Gateway stage to apply the changes.
6. F. Change the API Gateway route to add an X-Amz-Target header with a static value of 'Async' in the integration reques
7. G. Deploy the API Gateway stag apply the changes.

Correct Answer: A

- (Exam Topic 1)
A Developer is writing a mobile application that allows users to view images from an S3 bucket. The users must be able to log in with their Amazon login, as well as Facebook® and/or Google® accounts.
How can the Developer provide this authentication functionality?

1. A. Use Amazon Cognito with web identity federation.
2. B. Use Amazon Cognito with SAML-based identity federation.
3. C. Use AWS IAM Access/Secret keys in the application code to allow Get* on the S3 bucket.
4. D. Use AWS STS AssumeRole in the application code and assume a role with Get* permissions on the S3 bucket.

Correct Answer: A
Reference:
http://jayendrapatil.com/tag/iam-role/
https://docs.aws.amazon.com/sdk-for-javascript/v2/developer-guide/loading-browser-credentials-federated-id.ht

- (Exam Topic 2)
An Amazon RDS database instance is used by many applications to look up historical data. The query rate is relatively constant. When the historical data is updated each day, the resulting write traffic slows the read query performance and affects all application users.
What can be done to eliminate the performance impact on application users?

1. A. Make sure Amazon RDS is Multi-AZ so it can better absorb increased traffic.
2. B. Create an RDS Read Replica and direct all read traffic to the replica.
3. C. Implement Amazon ElastiCache in front of Amazon RDS to buffer the write traffic.
4. D. Use Amazon DynamoDB instead of Amazon RDS to buffer the read traffic.

Correct Answer: B
https://aws.amazon.com/rds/details/read-replicas/