The 3-2-1 backup rule, explained simply
Drives fail, laptops get stolen and ransomware encrypts everything it can reach. A backup plan has to survive all three.
- 3 copies of your data: the original plus two backups.
- 2 different types of storage, for example your laptop and an external drive.
- 1 copy offsite, such as cloud backup or a drive kept at another location.
Trap: an external drive that is always plugged in can be encrypted by ransomware along with your PC. Disconnect it after the backup, or use a cloud service that keeps older versions.
Once a month, restore one file from your backup. A backup you have never tested is only a hope.