A payments ledger must recover within 45 minutes of a regional outage, and no committed transaction may be lost. Which disaster recovery design meets both targets?
Show answer and explanation
Answer: C
A recovery point objective near zero requires that acknowledged writes exist in a second location before the client is told they succeeded. A multi-region configuration with synchronous commit across regions does this, and keeping the application tier already deployed in the second region keeps recovery time within the 45-minute target. Standard cross-region read replicas are asynchronous and can lose recent writes, and backup-based options have recovery points measured in hours and recovery times that include restoration work.
Why the other options are wrong
- A. Nightly exports can lose up to a day of transactions, so the recovery point is far outside the near-zero target. Manual restoration also makes the recovery time unpredictable.
- B. Coldline restores take time to copy and rebuild, and the backups are only as recent as the last snapshot. Both the recovery time and the data loss window exceed the requirements.
- D. Fifteen minutes of replication lag means up to fifteen minutes of committed writes can be lost. Rebuilding the application after a failure also adds time that threatens the 45-minute target.