Name the two age constraints
At synthetic review 10:00, backup completed 09:40 and last successful recovery rehearsal was yesterday 10:00. Local readiness requires backup age≤30 minutes and rehearsal age≤12 hours. The supplied rehearsal used this same configuration; no other evidence exists.
| Evidence | Age | Limit |
|---|---|---|
| Completed backup | 20 min | ≤30 min |
| Successful rehearsal | 24 h | ≤12 h |
Measure each age at the same instant
- Fix the review instant
- Subtract each evidence timestamp
- Require both independent limits
An attempted rehearsal without success evidence is not a newer successful rehearsal.
Is local readiness established?
Show the worked answer
No. Backup age 20 minutes passes, but rehearsal age 24 hours exceeds 12 by 12 hours. A recent backup does not satisfy the rehearsal condition.
Keep both outcomes
| Case | Decision | Reason |
|---|---|---|
| Backup 20 min | Pass freshness | Within 30 |
| Rehearsal 24 h | Fail readiness component | Beyond 12 |
Record which condition failed so the next task is a recovery rehearsal, not merely another backup copy.