How to Use a 3-2-1 Backup

One of those topics we often talk about in support and on our forums is being diligent about backups. At a minimum, an external hard drive and Time Machine are much better than no backups. But for a more robust backup strategy, think: 3-2-1. The 3-2-1 backup strategy is a good way to minimize data loss. Simply stated: keep three copies of your data, on two different types of media, with one copy stored offsite. Here’s a quick overview, with your DEVONthink databases as the example.

Three copies of your data: One copy is the database you’re working on. The second copy is on your primary backup. We advocate a local backup using an external hard drive and Time Machine or a similar snapshot-style backup application. This gives you immediate access to your backups in an emergency. The third copy is a redundant backup.

Backed up to two separated media: Your two backups should be stored on different media, ideally on a different type of media. So, if your primary backup is on an external hard drive, the second backup could be a network-attached storage (NAS) or an online backup via an appropriate backup application, e.g., Arq. But of course, a second external drive is better than no redundant backup.

With one offsite copy: An offsite copy is a safety measure in case of extreme circumstances. Fire, theft, floods, weather, etc. can affect a single geographic location, leaving you in a situation where your local backups, including redundant ones, could be lost. Many people still store backup hard drives in a separate physical location like a safety deposit box in a bank. Sounds old-fashioned, but that can come in handy if the worst happens. If your third copy is online, that counts as an offsite backup.

We hope this encourages you to stop and take a look at your data safety and start or resume your backups today!

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