AWS Certified Solutions Architect – Associate (SAA-C02) — Question 459

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

Amazon RDS Multi-AZ deployments utilize synchronous replication to a standby instance in a different Availability Zone, which guarantees zero data loss (an RPO of 0) in the event of a failure. Read replicas and AWS DMS CDC tasks rely on asynchronous replication, which introduces replication lag and cannot guarantee an RPO of under 1 second. Storage auto-scaling only manages disk capacity and does not address database redundancy or recovery objectives.