CompTIA Security+ (SY0-701)Security ArchitectureHard
A backup policy requires full backups every 12 hours. A production database server fails 9 hours after the most recent successful backup completed. The organization's disaster recovery plan defines an RPO of 12 hours. What is the actual amount of data lost, and does it satisfy the defined RPO?
- A12 hours lost; RPO is not satisfied
- B3 hours lost; RPO is satisfied
- C9 hours lost; RPO is satisfied
- D9 hours lost; RPO is not satisfied
Show answer & explanationAnswer & explanation
Correct answer: C. 9 hours lost; RPO is satisfied
Data loss equals the time between the last successful backup and the failure, which is 9 hours. Since 9 hours is less than or equal to the defined RPO of 12 hours, the actual loss falls within the acceptable target, satisfying the RPO.
Why the other options are wrong
- A. 12 hours is the backup interval/RPO target, not the actual loss in this scenario.
- B. 3 hours is not derived from the given timeline; the failure occurred 9 hours after backup.
- D. 9 hours is correct for loss, but it does satisfy the RPO since 9 ≤ 12.
Recovery Point Objective (RPO)
The maximum acceptable amount of data loss, measured in time, that an organization can tolerate following a disruption.
- Actual data loss = time since last successful backup to the point of failure
- RPO is satisfied when actual loss ≤ target RPO
- Shorter RPOs require more frequent backups or replication, increasing cost
Memory trick: 'RPO is the loss limit; the clock since last backup is the actual toll.'