AWS Certified Solutions Architect – Associate (SAA-C03) — Question 676

A company wants to migrate an on-premises legacy application to AWS. The application ingests customer order files from an on-premises enterprise resource planning (ERP) system. The application then uploads the files to an SFTP server. The application uses a scheduled job that checks for order files every hour.

The company already has an AWS account that has connectivity to the on-premises network. The new application on AWS must support integration with the existing ERP system. The new application must be secure and resilient and must use the SFTP protocol to process orders from the ERP system immediately.

Which solution will meet these requirements?

Answer options

• A. Create an AWS Transfer Family SFTP internet-facing server in two Availability Zones. Use Amazon S3 storage. Create an AWS Lambda function to process order files. Use S3 Event Notifications to send s3:ObjectCreated:* events to the Lambda function.
• B. Create an AWS Transfer Family SFTP internet-facing server in one Availability Zone. Use Amazon Elastic File System (Amazon EFS) storage. Create an AWS Lambda function to process order files. Use a Transfer Family managed workflow to invoke the Lambda function.
• C. Create an AWS Transfer Family SFTP internal server in two Availability Zones. Use Amazon Elastic File System (Amazon EFS) storage. Create an AWS Step Functions state machine to process order files. Use Amazon EventBridge Scheduler to invoke the state machine to periodically check Amazon EFS for order files.
• D. Create an AWS Transfer Family SFTP internal server in two Availability Zones. Use Amazon S3 storage. Create an AWS Lambda function to process order files. Use a Transfer Family managed workflow to invoke the Lambda function.

Correct answer: D

Explanation

Option D is correct because deploying an internal AWS Transfer Family server across two Availability Zones ensures a highly available and secure endpoint over the existing private connection to the on-premises ERP. Utilizing a Transfer Family managed workflow to trigger an AWS Lambda function allows for immediate order processing as soon as files are uploaded. Other options are incorrect because they either expose the server to the internet, lack multi-AZ redundancy, or rely on scheduled polling rather than event-driven real-time processing.