Which solution will meet these requirements MOST cost-effectively?
Create an AWS Storage Gateway File Gateway. Schedule daily Windows server backups. Save the data to Amazon S3. During a disaster, recover the on-premises servers from the backup. During tailback, run the on-premises servers on Amazon EC2 instances.
Create a set of AWS CloudFormation templates to create infrastructure. Replicate all data to Amazon Elastic File System (Amazon EFS) by using AWS DataSync. During a disaster, use AWS CodePipeline to deploy the templates to restore the on-premises servers. Fail back the data by using DataSync.
Create an AWS Cloud Development Kit (AWS CDK) pipeline to stand up a multi-site active-active environment on AWS. Replicate data into Amazon S3 by using the s3 sync command. During a disaster, swap DNS endpoints to point to AWS. Fail back the data by using the s3 sync command.
Use AWS Elastic Disaster Recovery to replicate the on-premises servers. Replicate data to an Amazon FSx for Windows File Server file system by using AWS DataSync. Mount the file system to AWS servers. During a disaster, fail over the on-premises servers to AWS. Fail back to new or existing servers by using Elastic Disaster Recovery.
Explanations:
This option relies on daily backups and does not meet the RTO of 15 minutes or RPO of 5 minutes since it requires restoring from backups, which can take significantly longer than the specified RTO and RPO. Additionally, it does not provide native failover capabilities.
While AWS DataSync can replicate data to Amazon EFS, the use of CloudFormation templates for server restoration during a disaster does not support the rapid failover required for the 15-minute RTO. Also, this solution may not provide the needed fallback capabilities efficiently.
This option describes a multi-site active-active environment, but using thes3 synccommand for data replication does not guarantee the RPO of 5 minutes, and DNS swaps may also not achieve the required RTO. Additionally, this solution lacks specific failback capabilities.
AWS Elastic Disaster Recovery enables continuous replication of on-premises servers with low RTO and RPO. By using Amazon FSx for Windows File Server, it provides native failover and fallback capabilities, allowing for rapid switching during a disaster, thus meeting both RTO and RPO requirements effectively.
I classify that the answer is:
Use AWS Elastic Disaster Recovery to replicate the on-premises servers. Replicate data to an Amazon FSx for Windows File Server file system by using AWS DataSync. Mount the file system to AWS servers. During a disaster, fail over the on-premises servers to AWS. Fail back to new or existing servers by using Elastic Disaster Recovery.