ISC2 Systems Security Certified Practitioner (SSCP) Practice Question

Enabling cross-Region automated backups copies the RDS instance's daily snapshot and transaction logs to Amazon S3 in a secondary Region with a typical RPO of about 5 minutes. No standby database is kept running, so ongoing cost is limited to the incremental storage and data-transfer charges. In the event of a regional outage, operations can restore the latest point-in-time backup into a new RDS instance in the target Region and point applications to it, a process that AWS estimates can be completed well within 60 minutes.

A cross-Region read replica would satisfy the RPO and RTO but requires a continuously running replica instance, increasing cost. Multi-AZ only protects within a single Region, so it does not meet the cross-Region requirement. Using AWS DMS with a pre-created target still incurs replication instance costs and delays associated with provisioning and cutover, making it less cost-effective and potentially longer than the required RTO.