SAA-C03 Design Resilient Architectures Practice Question

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✗

  Configure an RDS Read Replica in a different region and promote it if the primary fails.

  Why it's wrong here

  While this provides regional disaster recovery, promoting a read replica to a standalone instance is a manual or semi-automated process that takes significantly longer than a standard Multi-AZ failover. It is not the fastest way to recover from an instance-level failure within the same region.

• ✓

  Enable RDS Multi-AZ deployment.

  Why this is correct

  RDS Multi-AZ is specifically designed for high availability. It maintains a synchronous secondary standby in another AZ. Upon detecting a failure, RDS automatically initiates a failover process. This is the fastest, most reliable way to maintain database availability and minimize downtime for mission-critical applications without manual intervention.

• ✗

  Take hourly automated snapshots and restore from the latest snapshot upon failure.

  Why it's wrong here

  Restoring from a snapshot involves creating a new database instance, which can take several minutes to hours depending on the database size. This results in a very high RTO, which is unsuitable for mission-critical applications that require minimal downtime and continuous availability during unexpected database infrastructure failures.

• ✗

  Back up the database to S3 and use a standby EC2 instance to run a database engine.

  Why it's wrong here

  This self-managed approach is prone to human error and adds significant complexity to the recovery process. It lacks the seamless, automated failover capabilities provided by RDS Multi-AZ, leading to a much longer and less predictable RTO, making it an inferior choice for mission-critical production database environments.