Choosing a Backup Strategy: The 3-2-1 Rule Explained

A good backup plan is simple: more than one copy of your files, in more than one place, that you can actually get back. The 3-2-1 rule is the easiest way to get there.

The 3-2-1 rule

• 3 copies of your important data: the original plus two backups.
• 2 different types of storage, for example your computer and an external drive or a network storage device (NAS).
• 1 copy off-site, usually in the cloud, so a fire, flood, theft or hurricane at the office does not take everything at once.

Full vs. incremental, in plain words

• Full backup: copies everything. It is the slowest and uses the most space, but it is complete on its own.
• Incremental backup: after the first full copy, it only saves what changed since the last backup. It is fast and small, and most modern backup tools work this way automatically.

You do not need to manage this yourself. What matters is that the first full backup finishes and the small daily ones keep running.

Cloud vs. local

• Local (external drive or NAS): fast to restore large amounts of data, works without internet, but can be lost, stolen or damaged along with the computer.
• Cloud: safe from local disasters and available anywhere, but the first upload and large restores depend on your internet speed.

The best answer is usually both: a local copy for speed and a cloud copy for safety.

Why versioning matters

Versioning means the backup keeps older copies of each file, not just the latest one. This protects you when a file is accidentally overwritten, corrupted or encrypted by ransomware. Without versions, a backup can faithfully copy the damaged file and overwrite your good copy.

What to back up

• Documents, spreadsheets, photos and scanned files.
• Accounting and business application data (check where the program stores its company file).
• Email, calendars and contacts.
• Shared files on a server or NAS.
• Browser bookmarks and important settings.

Microsoft 365 data

Microsoft keeps its service running, but it does not promise long-term recovery of everything you delete. Deleted items in Outlook, OneDrive and SharePoint are kept only for a limited time. If your business relies on Microsoft 365, a separate Microsoft 365 backup is worth considering.

Laptops

Laptops travel, get dropped and get stolen. Make sure laptop files are backed up automatically to the cloud (for example with OneDrive folder backup) so nothing depends on someone remembering to plug in a drive.

A simple starting point

1. List where your important data lives (computers, server, Microsoft 365, accounting software).
2. Set up an automatic local backup and an automatic cloud backup.
3. Confirm both keep older versions.
4. Test a restore so you know it works.

Published on - 01-01-1970 05:30am