What is the 3-2-1 rule for backing up your data?
The 3-2-1 rule is a data backup framework that helps protect your files from loss or disaster. Originated by photographer Peter Krogh in 2009, this principle recommends keeping three copies of your data across two types of media, with one copy stored offsite. It matters because losing important files to hardware failure, disasters or theft can be devastating, and this rule provides a practical safeguard against such scenarios.
The rule works by emphasising redundancy: if you keep all copies in one location, a single disaster like a fire or flood could destroy everything. By spreading copies across different devices and locations, you protect against multiple failure scenarios. The framework has evolved over time to accommodate modern technology and cloud services, with many people now using combinations such as a laptop, external hard drive and cloud storage. Additionally, cybersecurity threats like ransomware have prompted updates to the rule, as offsite copies remain vulnerable if networked.
- The 3-2-1 rule: keep three data copies on two media types, one offsite
- It protects against hardware failure and physical disasters
- The framework adapts to modern cloud storage and security needs
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The 3-2-1 rule is a straightforward framework for protecting important files from being lost permanently. Created by photographer Peter Krogh in 2009, the approach recommends keeping three copies of your data, using two different types of storage device, with at least one copy kept in a separate physical location.
The strategy matters because storing all your files in one place leaves them vulnerable to a single disaster or failure. By spreading copies across different devices and locations—such as your computer, an external hard drive and cloud storage—you protect against various risks including hardware failure, theft and physical damage from fire or flooding.
The approach has evolved alongside modern technology, with many people now incorporating cloud services into their backup plans. Cybersecurity threats like ransomware have also emphasised the value of keeping one backup copy disconnected from the internet, to ensure it remains protected if your main systems are compromised.