A Brief Introduction to 3-2-1 Backup

A Brief Introduction to 3-2-1 Backup
4 min read
30 December 2022


Nowadays, most organizations recognize the value of data protection and backup in order to avoid the negative effects of data loss on their operations. Maintaining access to data is critical in the event of disruptions caused by inadvertent deletions and hardware failure, as well as more serious incidents such as natural disasters or malware attacks.

It may appear that recovering from a single copy of essential data is adequate. The 3-2-1 backup rule, on the other hand, lies at the foundation of every solid data security strategy. This guideline is now a widely understood practice within the IT sector and beyond. Information security specialists and government agencies such as the Cybersecurity and Infrastructure Security Agency (CISA) in the United States propose the 3-2-1 backup rule (in the Data Backup Options document by US-CERT).

3-2-1 backup rule includes:

·Keep at least 3 copies of data.

·Store 2 backup copies on different storage media.

·Store 1 backup copy offsite.


Keep at least 3 copies of data.

The original production data and two backup copies are represented by three copies. Keeping three copies of data is the minimal minimum necessary to ensure recovery in every failure situation, to keep recovery targets low, and to avoid a single point of failure.

As a result, the more backup copies you have, the less likely you are to lose them all at once. Because a single backup is kept in the same area as the main data, any calamity that affects your primary data might also harm your secondary copy.

Store 2 backup copies on different storage media.

Having all of your backups on the same type of storage media increases the likelihood of both devices failing at about the same time due to a fault or ordinary wear and tear.

To follow the 3-2-1 rule, keep your primary data and backup copies on at least two distinct storage media, such as internal or external hard drives, NAS, tape, and others.

Store 1 backup copy offsite.

Keeping all of your backups in one location is not advised since they might be completely destroyed in a natural catastrophe or a building issue such as an office fire. As a result, the 3-2-1 backup plan recommends storing one or more backup copies in a remote place, such as another city, state, nation, or continent. A remote location in this situation either be physical offsite storage or the cloud.

Keep in mind that while remote backups boost your odds of recovery, having local copies allows faster and easier recovery. The 3-2-1 backup rule should be part of a complete disaster recovery strategy to maintain company continuity and prepare for all potential threats.

Required measures in addition to the 3-2-1 rule

Companies that basically adhere to this 3-2-1 principle and further customize their data backup policy to create their own "3-2-1-#-#-#" rule There are probably many. Other considerations include whether additional copies of data are intentionally kept offline (air-gapped) or whether additional recovery verification is required.

With regards to the 3-2-1 backup rule, and enterprise-level backup in general, we believe the following key points should be considered:


Ease of use

Security cost and capacity

Recovery Time Objective (RTO) and Recovery Point Objective (RPO)

On-Premises vs. Cloud Backup Targets

Data integrity protection


For decades, the 3-2-1 backup rule has been the most successful technique to data security. By storing three distinct copies of your data, two on different storage medium and one offshore, you dramatically lower the likelihood of losing all of your data. However, as threats develop, so should your security measures. The term "responsibility" refers to the act of determining whether or not a person is responsible for his or her own actions.

In case you have found a mistake in the text, please send a message to the author by selecting the mistake and pressing Ctrl-Enter.
Zoe Ye 2
Joined: 1 year ago
Comments (0)

    No comments yet

You must be logged in to comment.

Sign In / Sign Up