CompTIA DataSys+ (DS0-001)Database Management and MaintenanceHard
A database administrator is tasked with implementing a disaster recovery solution that allows for minimal data loss (RPO) and quick recovery time (RTO) for a critical production database. The database is hosted on-premises. Which of the following solutions BEST meets these requirements?
- AReplication using snapshot-based publications.
- BDaily full backups to tape, stored off-site.
- CLog shipping with hourly log backups.
- DDatabase mirroring with a synchronous commit mode.
Show answer & explanationAnswer & explanation
Correct answer: D. Database mirroring with a synchronous commit mode.
Database mirroring in synchronous commit mode provides near-zero data loss (RPO) because transactions are committed on both the principal and mirror servers before the client receives confirmation. It also offers rapid failover (low RTO) as the mirror is always up-to-date and ready to take over with minimal interruption.
Why the other options are wrong
- A. Replication, especially snapshot-based, is typically used for data distribution and reporting, not for high-availability disaster recovery with minimal RPO/RTO. It has higher latency and potential for data divergence.
- B. Daily full backups to tape would result in an RPO of up to 24 hours and a high RTO due to the time required to restore from tape, failing to meet the 'minimal data loss' and 'quick recovery time' requirements.
- C. Log shipping with hourly log backups would result in an RPO of up to one hour (data loss since the last log backup) and requires manual intervention for failover, leading to a higher RTO than mirroring.
Recovery Point Objective (RPO)
The maximum acceptable amount of data (measured in time) that can be lost from a database during a disaster.
- A lower RPO means less data loss is tolerated.
- RPO is typically achieved through frequent backups or real-time data synchronization.
- Synchronous solutions offer the lowest RPO.
Memory trick: RPO is data lost, RTO is time spent down.