AWS Certified Solutions Architect – Associate (SAA-C03) — Question 269

A company runs a fleet of web servers using an Amazon RDS for PostgreSQL DB instance. After a routine compliance check, the company sets a standard that requires a recovery point objective (RPO) of less than 1 second for all its production databases.

Which solution meets these requirements?

Answer options

• A. Enable a Multi-AZ deployment for the DB instance.
• B. Enable auto scaling for the DB instance in one Availability Zone.
• C. Configure the DB instance in one Availability Zone, and create multiple read replicas in a separate Availability Zone.
• D. Configure the DB instance in one Availability Zone, and configure AWS Database Migration Service (AWS DMS) change data capture (CDC) tasks.

Correct answer: A

Explanation

Enabling a Multi-AZ deployment for Amazon RDS uses synchronous replication to copy data to a standby instance in another Availability Zone, which guarantees an RPO of zero (less than 1 second) during a failover. In contrast, read replicas and AWS DMS CDC tasks use asynchronous replication, which can result in replication lag and cannot guarantee an RPO of under 1 second. DB instance auto-scaling adjusts storage capacity but does not provide high availability or replication for disaster recovery.