Everyone agrees backups matter, and almost nobody has them until the first disaster. The 3-2-1 rule is the entire science of not losing your files, compressed into three numbers you can set up in an afternoon.
The rule
- 3 copies of anything you can't afford to lose — the original plus two backups.
- 2 different kinds of storage — say, your computer and an external drive, or your computer and cloud storage. Two copies on the same laptop die together.
- 1 copy somewhere else — physically elsewhere. Fire, flood, and burglary take the computer and the drive sitting next to it. Cloud storage satisfies this beautifully.
What this looks like in real life
For a typical small business: your working files live on your computer (copy 1). An external drive or the office computer syncs a backup weekly (copy 2, second kind of storage). A cloud service — Google Drive, Dropbox, OneDrive, Backblaze — syncs continuously (copy 3, elsewhere). Total cost: an external drive once, plus a few dollars a month. Total setup: one afternoon, then it runs itself.
The two mistakes that break backups
- Backups that need remembering. A backup you do manually "every Friday" stops the week things get busy — which is the week before the disaster, always. Automate everything; humans are the unreliable component.
- Backups nobody has ever restored. A backup you've never opened is a hope, not a backup. Twice a year, pick a random file and actually restore it. Five minutes, and now you know.
What about your website?
Same rule, and check who's doing which copy: many hosts back up your site automatically (we keep nightly copies on separate storage — that's copies 2 and 3 handled). Worth confirming with your host: how often, kept how long, and how fast can they restore? If the answer is a shrug, that tells you something too.