Snapshots are a way to restore in a point in time the database by performing a volume snapshot. This is a managed activity that uses S3 managed buckets. It is pretty common to think that these snapshots can be managed from the user's end because the are already in S3 and apply lifecycle policies to archive them in Glacier; but this is a misconception. RDS snapshots are only managed through the API with the capability to retain up to 7 days of snapshots. These snapshots can be copied across regions to synchronize data and recover from a regional disaster