3 2 1 Backup Rule: What Is It And How To Do It Right | Zerto

The 3-2-1 Rule in Data Backup

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The 3-2-1 rule is a data backup strategy first developed by photographer Peter Krogh and presented in his book on digital asset management in 2005. Since then, this rule has become the industry standard for data protection and disaster readiness.  

What Is the 3-2-1 Rule in Data Backup ?

The 3-2-1 rule can be broken down into three simple parts:

  • Keep 3 copies of data, including all production data and two backup copies.
  • Store backup copies on 2 different types of storage, including any combination of on-premises, cloud, or offline options.
  • Ensure 1 backup copy is stored at on off-site location, such as a public cloud server.

What are the Benefits of the 3-2-1 Rule?

The key to the 3-2-1 rule is redundancy. By creating multiple copies of production data and storing them in disparate locations, organizations bolster resilience in the event of a major disaster. Should something impact copy one, copy two will be safe in its own storage medium, allowing for easy and fast recovery. And since an organization’s data is the backbone of its operations, this enhanced resilience and recoverability is crucial to business sustainability and success.

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How Does Zerto Enable Fulfillment of the 3-2-1 Rule?

One of the core features of the Zerto solution is one-to-many replication , which allows a VM to simultaneously replicate to several target platforms while also replicating to a local copy or second remote site, all with write-order fidelity. By its root function, this key feature fulfills the 3-2-1 rule, and it folds right into all the other industry-leading aspects of Zerto:

  • Continuous Data Protection. Zerto replicates your data every few seconds and records the full state of all storage environments in its unique granular journal. This replication occurs in the background, with no impact on production.
  • Easy, Fast Deployment. Quick and easy to set up, software-only Zerto is also platform and vendor agnostic, so your organization can use it to back up and protect data regardless of storage locations, whether on-premises or in the cloud.
  • One Simple, Easy-to-Use Solution. Regardless of storage type or location—even if your datacenter is complex and spread across several sites—the Zerto interface is the same, so you benefit from continuity of experience and execution as you grow and expand.

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Other Resources

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Resource Center

Discover and access content from Zerto and 3rd parties (IDC, Gartner, ESG, etc.) related to backup and recovery.

What is Continuous Data Protection (CDP)?

Learn about continuous data protection and how this protection approach allows for data restore to any point in time with high granularity.

Data Protection Series

Read about trends, best practices, and technologies, like CDP, that help to protect data and prevent data loss in order to keep businesses running.

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Learn about Zerto and how it can help you solve your data protection and recovery challenges.