A company's disaster recovery plan requires that a copy of its RDS database snapshots exist in a second, geographically distant AWS region, but RDS automated backups and manual snapshots are stored only in the region where the DB instance runs. What should the team do to meet this requirement?
- Manually copy the RDS snapshot to the second region, which creates an independent snapshot there that can be used to restore a new DB instance in that region
- Enable Multi-AZ, which automatically stores a duplicate snapshot in a second region
- Rely on the default automated backup behavior, which already replicates snapshots cross-region
- Convert the DB instance to Aurora, since only Aurora snapshots can be copied across regions
Why A? And why not the others?
Correct answer: A. Manually copy the RDS snapshot to the second region, which creates an independent snapshot there that can be used to restore a new DB instance in that region
RDS snapshots, whether automated or manual, live in the same AWS region as the source DB instance by default, and the supported way to get a durable copy in another region is to explicitly copy the snapshot, which produces an independent snapshot in the destination region that can restore a new DB instance there if the primary region becomes unavailable. The option describing Multi-AZ is wrong because Multi-AZ standbys are confined to Availability Zones within the same region for synchronous replication; the feature has no cross-region component and does not touch snapshot storage at all. The option describing default automated backup behavior is wrong because automated backups do not automatically leave their source region; without an explicit copy action, no cross-region copy exists. The option describing converting to Aurora is wrong because standard RDS engines, including MySQL, PostgreSQL, MariaDB, SQL Server, and Oracle, all support manual cross-region snapshot copying; this capability is not exclusive to Aurora.
Source: AWS RDS documentation: copying a DB snapshot