Untested Backups Are A Guess
A backup you have never restored is a hope, not a guarantee. Files can be silently corrupt, missing log segments can block recovery, and runbooks can drift out of date. A disaster recovery drill rehearses the full restore so you learn the truth in practice, not during a real outage.
The Two Targets
Drills validate two numbers from your recovery plan:
- RPO, recovery point objective: the maximum acceptable data loss, measured as the time between the last recoverable state and the failure.
- RTO, recovery time objective: the maximum acceptable downtime, how long the full recovery takes.
A drill measures both for real and compares them to the promised targets.
What A Good Drill Does
- Restore to an isolated environment from real backups, never against production.
- Replay logs to a target time to exercise point in time recovery.
- Verify integrity: row counts, checksums, and application smoke tests, not just that the process finished.
- Time it and write down gaps, then fix the runbook and tooling before the next drill.
Running drills on a schedule keeps the process and the people sharp, so the real event is rehearsed rather than improvised.
Key idea
A disaster recovery drill restores real backups to an isolated environment, verifies integrity, and measures actual RTO and RPO against targets, turning untested hope into proven, rehearsed recovery.