Amazon Exam SOA-C03 Topic 2 Question 3 Discussion

According to the AWS Cloud Operations and Disaster Recovery documentation, the active-active multi-Region architecture provides the lowest possible RTO and RPO among all disaster recovery strategies. In this approach, workloads are deployed and actively running in multiple AWS Regions simultaneously. All data is continuously replicated in real time between Regions using fully managed replication services, ensuring zero data loss (zero RPO).

Because both Regions are active and capable of handling requests, failover between them is instantaneous, meeting the RTO of less than 10 minutes. Amazon Route 53 is used with weighted or latency-based routing policies and health checks to automatically route traffic away from an impaired Region to the healthy Region without manual intervention.

In contrast:

Pilot Light Architecture maintains only a minimal copy of the environment in the secondary Region. It requires time to scale up infrastructure during a disaster, resulting in longer RTO and potential data loss (non-zero RPO).

Warm Standby Architecture keeps partially running infrastructure in the secondary Region. Although faster than pilot light, it still requires scaling and synchronization, resulting in higher RTO and RPO compared to active-active.

Backup and Restore (option D) relies on periodic backups and restores data when needed. This approach has the highest RTO and RPO, unsuitable for mission-critical workloads demanding high availability and zero data loss.

Therefore, based on AWS-recommended disaster recovery strategies outlined in the AWS Cloud Operations and Disaster Recovery Guide, the Active-Active Multi-Region architecture (Option C) is the only approach that guarantees RTO <10 minutes and RPO = 0, achieving continuous availability and business continuity across Regions.