The 3-2-1 Backup Rule Explained
Hard drives fail, phones get lost and ransomware can lock files. A good backup plan makes all of these annoyances instead of disasters. The 3-2-1 rule is easy to remember and works for individuals and small businesses.
What 3-2-1 means
- 3 copies of your data: the original plus two backups.
- 2 different types of storage, for example an external drive and cloud storage.
- 1 copy off-site, so a fire, theft or flood cannot destroy everything.
A simple home setup
- Your files live on your computer (copy 1).
- An external drive backs up automatically using the built-in system backup tool (copy 2).
- An encrypted cloud backup holds a third copy off-site.
Protect backups from ransomware
Ransomware can encrypt connected drives. Keep one backup disconnected or use cloud storage with version history, so you can restore older files.
Encrypt and test
Encrypt backups, especially off-site ones. Every few months, restore a file to make sure the backup actually works.
What to back up first
Photos, documents, tax and financial records, and exports of important data. Apps can usually be reinstalled, so focus on your own files.
Key takeaway: Three copies, two kinds of storage, one off-site. Automate it, encrypt it and test a restore occasionally.
