Which solution will meet these requirements?
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.
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.
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.
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.
Explanations:
While this option uses an internet-facing SFTP server and Amazon S3 storage with Lambda processing, it does not specify that the server should be internal to ensure secure integration with the on-premises ERP system. Additionally, the reliance on S3 Event Notifications means file processing may not be immediate, as it relies on object creation events.
This option uses an SFTP server with Amazon EFS storage, which is suitable for file sharing, but the processing using a Lambda function via Transfer Family managed workflow does not guarantee immediate processing of order files, especially if the files are not stored in a consistent state. Also, having the SFTP server in only one Availability Zone introduces a single point of failure, compromising resilience.
Although this option uses an internal SFTP server in multiple Availability Zones, which enhances resilience, it relies on periodic checks using EventBridge Scheduler. This may not provide immediate processing for order files as required. Moreover, using EFS may not be the best fit for processing and might introduce complexity in handling file states.
This option specifies an internal SFTP server in two Availability Zones, ensuring resilience and security. Using Amazon S3 storage allows for efficient file management, and the use of a Transfer Family managed workflow to invoke a Lambda function allows for immediate processing of order files upon upload, meeting the requirement for immediate integration with the ERP system.
I weigh that the answer is:
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.