The 3-2-1-1-0 Backup Rule
Three copies, two media, one offsite, one offline, zero recovery errors. The modern reading of the backup rule, and where a physical air gap sits inside it.
What Each Number Actually Requires
Plain definitions for each digit in the rule, and what a modern ransomware resistant estate needs to satisfy them.
3 copies of your data
Keep at least three copies of every important dataset. The live production copy counts as one. Two independent backup copies protect against the failure of any single storage system, and against the ransomware playbook that targets a single backup platform first.
- Production is copy one
- Two independent backups
- No single storage dependency
2 different media
Spread the copies across at least two different storage media. Disk and object storage. Object and tape. Cloud and physically disconnected disk. Different media fail differently and are targeted differently, so a single class of failure or exploit cannot take every copy at once.
- Diverse storage types
- Diverse vendors and firmware
- Diverse attack surfaces
1 copy offsite
At least one copy lives away from the primary site, whether that is another data centre, another region or a Firevault Bunker. Fire, flood and localised destructive attacks stop at the site boundary, and the offsite copy remains available to rebuild from.
- Different site or region
- Independent power and network
- Survives physical disaster
1 copy offline
One copy is offline and out of reach of the production network. This is the modern addition to the classic 3-2-1 rule and the one that ransomware operators cannot defeat remotely. Firevault Offline Secure Storage is designed specifically to be this copy, with Layer 1 disconnection and a tamper evident audit trail.
- No network path when offline
- Out of band switching only
- Tamper evident connection log
0 errors on recovery
A backup that has never been restored is not a backup, it is a belief. The zero on the end of the rule requires regular, verified test restores that prove the copies are readable and consistent. A gold copy that cannot be restored on demand is worse than no plan at all.
- Scheduled test restores
- Integrity verified end to end
- Runbooks proven, not written
Read the pillar guide, or continue with the comparison against immutable backup.
The 3-2-1-1-0 Backup Rule, Common Questions
Straight answers on how Offline Secure Storage® behaves in practice.
Add the offline 1 to your backup strategy
Talk to the Firevault team about adding a Layer 1 offline gold copy so your estate satisfies the modern 3-2-1-1-0 rule.
Takes about 2 minutes. No account needed.