The company wants a business-continuity plan in AWS in case their main on-premises application (running on physical servers that also host other apps) fails. The app uses MySQL and the OSs are EC2-compatible. Which approach provides the required continuity with the least operational overhead?

AWS Elastic Disaster Recovery (DRS) is the most suitable solution for achieving business continuity with minimal operational overhead. It uses a lightweight replication agent installed on the source servers (including those running MySQL) to continuously replicate data to a staging area in the target AWS Region. This provides near real-time replication, enabling a low Recovery Point Objective (RPO). When a disaster occurs, DRS automates the conversion of replicated servers into EC2 instances, ensuring a low Recovery Time Objective (RTO). The ability to regularly perform failover and fallback tests confirms readiness without significant manual effort. The other options are less optimal: Installing the AWS Replication Agent and manually launching test instances for drills, then cutting over, involves more manual steps and operational overhead compared to the automated orchestration of DRS. Using DMS with Aurora and SCT for data synchronization, combined with manual EC2 instance setup, is complex and introduces more components to manage, increasing operational overhead. AWS Storage Gateway Volume Gateway is primarily for hybrid storage and backup, not continuous application-level disaster recovery, and would require significant manual effort to restore and configure applications on EC2 during a failure.