What Is the 3-2-1 Backup Strategy?

What Is the 3-2-1 Backup Strategy?

There are many types of data backup strategies, but one in particular has established itself as one of the go-to baseline strategies: the 3-2-1 backup strategy.

Invented by photographer Peter Krogh in his 2009 book Digital Asset Management for Photographers, the 3-2-1 backup strategy asks you to:

• Maintain three copies of your data: the original and at least two copies. 
• Use two different types of media (i.e., devices) for storage in case one type is affected by some kind of adverse event such as a hack.
• Always keep one copy of the data off-site to eliminate the potential for data loss due to a site-specific failure.

Advantages of the 3-2-1 Backup Strategy

The primary advantage of the 3-2-1 backup strategy is that it accounts for various ways data can be lost. It also provides flexibility around how you back up your data as it is a general rule and hence considered a baseline strategy. Furthermore, it’s simple and easy for anyone from individuals to big companies to follow, and it’s easily applied to any type of data storage scale or situation.

Disadvantages of the 3-2-1 Backup Strategy

The 3-2-1 data backup strategy has been around for 14 years, which is a long time in the fast-moving tech world. As such, it’s probably due for an update to account for new types of ways data can be lost.

What’s changed since the 3-2-1 backup strategy was invented?

Historically, the most common causes of data loss have been:

• Database migration
• Software corruption
• Local disaster
• Hard drive failure
• Theft
• Human error

But now ransomware attacks are also very common, leading to the need to create ransomware-specific data backup strategies such as snapshots.

If you get hit by a successful ransomware attack, every second your systems are down is incredibly costly, and the traditional 3-2-1 backup may not totally protect your backup systems. This, in turn, may force you into manual recovery, which will make it impossible for you to meet your recovery time objective (RTO).

A newer backup strategy adds another “1” to the 3-2-1 backup strategy to enhance data protection.

The 3-2-1-1 Backup Strategy

For an extra layer of protection, IDC recommends storing one copy of your data on immutable storage or in the cloud. Unlike with data encryption, immutability has no key. Hence, there’s no way to “read” or reverse it. With this extra step, the 3-2-1 backup strategy becomes an updated and far more effective 3-2-1-1 backup strategy.

3-2-1 Backup Strategy Best Practices

Regardless of if you use the 3-2-1 strategy or the 3-2-1-1 strategy, you still need to follow the basics of data backup best practices, which include:

1. Regular backups: Create a schedule for your backups that also includes when and how you’ll validate and test the backup (see number 3 below). Essentially, you should back up your data as frequently as possible and at such a cadence that, if data were lost, it wouldn’t be an unacceptable loss.
2. Automation: Manual backups are error-prone while automated backups will ensure you always have the latest versions stored securely.
3. Backup testing: Since backups can fail and lead to data getting corrupted, it’s essential to perform regular data verification and restore testing.

And remember, a 3-2-1 backup strategy should only ever be viewed as part of a larger backup and recovery plan, one that also includes things like air-gapped storage, malware scanning, and data encryption. 

Best Data Backup Solution

Any data backup strategy requires a good data backup solution to support it. 

The best data backup solutions provide a backup architecture that is fast enough to back up and restore data when it matters most but also big enough to consolidate your data silos—including your backup appliances. The best backup solutions are also, of course, affordable and secure. Learn more about Pure Storage and how it supports backup strategies.