SOA-C02 Reliability and Business Continuity 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.

• ✗

  Use AWS Backup to schedule daily backups and restore in another region.

  Why it's wrong here

  AWS Backup's scheduled backups can copy snapshots to a different region, but a daily backup cadence creates a recovery point objective (RPO) of up to 24 hours, which far exceeds the required 5-minute RPO. Restoring a table from a backup into another region typically takes minutes to hours, depending on table size and partition count, so the 1-hour RTO is not guaranteed. Moreover, this approach requires manual or automated restore steps and does not provide native replication for continuous availability, making it unsuitable for rapid regional failover.

• ✓

  Enable DynamoDB global tables for the table.

  Why this is correct

  DynamoDB global tables replicate your table automatically and asynchronously across multiple AWS Regions, typically with sub-second latency, which easily satisfies a 5-minute RPO. Because every replica accepts reads and writes, you can fail over instantly by rerouting application traffic (e.g., via Route 53 health checks) to a healthy region, meeting the 1-hour RTO without needing to restore data. Global tables also handle conflict resolution using last-writer-wins, ensuring data consistency across regions and making them the correct managed solution for regional disaster recovery.

• ✗

  Enable point-in-time recovery (PITR) on the table.

  Why it's wrong here

  Point-in-time recovery (PITR) continuously backs up table changes to provide granular restore to any second within the last 35 days, but it only protects against accidental writes, deletes, or logical corruption. It does not replicate data to another region; the restore operation creates a new table in the same region, so a regional outage leaves the original table and its backups unavailable. Even if you copy the restored table to another region, the restore and copy process can take longer than the 1-hour RTO, and PITR alone cannot provide automatic failover.

• ✗

  Configure cross-region read replicas for the table.

  Why it's wrong here

  DynamoDB does not support cross-region read replicas as a native feature. While you might consider using a combination of DynamoDB Streams and a custom replication app to create read-only copies in other regions, that is complex and does not provide active-active failover or write availability in the secondary region. Global tables are the actual AWS service that handles multi-region replication, supporting both read and write operations, so the premise of this option is factually incorrect as a solution.

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