A company hosts a community forum using an ALB fronting Docker containers in Amazon ECS, with data in Amazon RDS for MySQL and container images in ECR. They require a disaster recovery SLA with an RTO ≤ 24 hours and RPO ≤ 8 hours. Which is the MOST cost-effective solution that meets these RTO/RPO targets?

The correct option describes a "cold standby" or "backup and restore" disaster recovery strategy, which is the most cost-effective for the given RTO/RPO. Storing Docker images in ECR in two regions and regularly copying RDS snapshots ensures data availability. CloudFormation templates allow for rapid, automated deployment of infrastructure in the secondary region when needed, meeting the RTO. Eight-hour snapshot intervals meet the RPO. The first incorrect option, deploying identical resources in two regions and using multi-region replication, is a "hot standby" approach, which is more expensive than necessary for the specified RTO/RPO. The third incorrect option, while using CloudFormation, relies on importing Docker images and restoring from S3 backups, which can be slower and more complex than using ECR directly and RDS snapshots. The fourth incorrect option, a "pilot light" approach with a cross-Region read replica, is more expensive than the "backup and restore" method because it maintains active, albeit minimal, infrastructure and a continuously replicated database, which is not required for the given RTO/RPO.