A company wants to use AWS for disaster recovery for an on-premises application. The company has hundreds of Windows-based servers that run the…

This solution directly addresses all the stringent requirements. AWS Elastic Disaster Recovery (DRS) is a purpose-built service for replicating entire servers (including OS, applications, and data) with RPOs of seconds and RTOs of minutes. It maintains a low-cost staging area and provides native, orchestrated failover and fallback capabilities. For the "common share," using AWS DataSync to replicate data to Amazon FSx for Windows File Server is the correct pattern. FSx provides a fully managed, native SMB file share that the recovered Windows EC2 instances can mount, ensuring application compatibility. This combination is the most operationally efficient and cost-effective for the stated DR objectives.

A. Daily backups result in an RPO of up to 24 hours and an RTO of many hours, failing to meet the 5-minute RPO and 15-minute RTO requirements.

B. Amazon EFS provides an NFS-based file system, which is not native for Windows servers that typically use SMB. A custom pipeline lacks the robust, native DR orchestration of DRS.

C. An active-active environment is significantly more expensive than a replication-based DR solution like DRS, violating the cost-effectiveness requirement. Amazon S3 is an object store, not a mountable file share.

1. AWS Elastic Disaster Recovery (DRS) User Guide

"What is AWS Elastic Disaster Recovery?": "AWS Elastic Disaster Recovery (AWS DRS) minimizes downtime and data loss with fast

reliable recovery of on-premises and cloud-based applications using affordable storage

minimal compute

and point-in-time recovery... This allows you to achieve RPOs of seconds and RTOs of minutes." This supports the RTO/RPO and cost-effectiveness claims for server replication.

2. AWS DataSync User Guide

"Getting started with AWS DataSync": "You can use DataSync to copy data between... on-premises storage systems such as Network File System (NFS) shares or Server Message Block (SMB) shares... and Amazon FSx for Windows File Server file systems." This confirms DataSync is the appropriate tool for replicating the on-premises SMB share to FSx.

3. Amazon FSx for Windows File Server User Guide

"What Is Amazon FSx for Windows File Server?": "Amazon FSx for Windows File Server provides fully managed native Microsoft Windows file systems... It's accessible from Windows... instances through the industry-standard Server Message Block (SMB) protocol." This confirms FSx is the correct target for the Windows common share.

4. AWS Elastic Disaster Recovery (DRS) User Guide

"Failback overview": The documentation details the built-in

simplified

and managed process for failing back replicated servers to the source infrastructure

confirming the "native fallback" requirement.