Library / Backup & disaster recovery
The 3-2-1-1-0 backup rule, explained simply
A simple rule that turns “we have backups” into “we can actually recover” — including from ransomware.
The rule
- 3 copies of your data
- 2 different types of storage
- 1 copy off-site
- 1 copy offline or immutable
- 0 errors when you test a restore
Why the last two matter most
Ransomware goes after backups first. An immutable or offline copy is the one attackers can’t encrypt, and a tested restore is the only proof your backups work.
Don’t forget Microsoft 365
Microsoft keeps the service running, but protecting your data is your responsibility. A dedicated Microsoft 365 backup covers mailboxes, OneDrive, SharePoint and Teams.