A backup rule that works: 3 copies, 2 kinds of storage, 1 away from the office

A copy of your files on the same computer is not a backup. If the machine is stolen, burned or locked by ransomware, the copy goes with it. The 3-2-1 rule is the standard answer.

What the rule says

• Keep 3 copies of important data: the original and two backups.
• Use 2 different kinds of storage, for example a server disk and cloud storage.
• Keep 1 copy away from your office, so a fire, flood or theft cannot reach it.

Many security teams add a fourth point: at least one copy that cannot be changed or deleted by anyone who gains access to your network. That is what stops ransomware from destroying your backups as well.

The step most people skip

A backup you have never restored is an assumption. Once a month, restore a few real files. Once or twice a year, restore a whole system to a spare machine and time it. The time it takes is your real recovery time.

Where to start

1. List the data you could not work without.
2. Find where each item lives today.
3. Set up automatic copies to a second place and to one away from the office.
4. Book the first test restore in your calendar.