What is 3-2-1 data backup

3-2-1 archiving is a popular method of data management with data backup. The aim of 3-2-1 archiving is to increase the security and availability of data in the event of failure, loss or damage. This method is based on three basic principles:

3 copies of your data: You should have at least three copies of your data. This means that in addition to the original, you should have two more backups. This way, even if one of the copies is damaged or lost, you will still have access to the data on the main host and one backup copy.

2 different media: Backups should be stored on at least two different media. These can be different types of hard drives, such as external HDDs, LTO magnetic tape, optical media (DVD, Blu-ray) or SSDs. The key is not to rely solely on one type of media, which reduces the risk of data loss due to media-specific failure.

1 copy in a different location: One of the backups should be stored in a different physical location from the other copies. This could be a different building, city or even the cloud. The idea is to protect against local disasters such as fire, flood or theft, which can destroy all the backups stored in one place.

Example of a 3-2-1 archiving implementation:

Original data: Data stored on the computer used for work - continuous access to the current copy.

Backup 1: Copy to external hard drive - plugged into Thunderbolt / USB port or network NAS server e.g. TerraMaster stored in the same office.

Backup 2: Copy on LTO media created on devices e.g. Symply LTO or in the cloud, and stored elsewhere.

Advantages of the 3-2-1 method:

Redundancy: Increasing the number of copies of data minimises the risk of total data loss.

Media diversity: Using a variety of media protects against media type-specific failure.

Geographical protection: Storing the backup at a different location protects against local disasters and local events such as fire, burglary, flooding, etc.


The 3-2-1 method is a simple but effective backup management strategy that increases data security and availability. Implementation of this strategy is a key element in data management for any organisation, regardless of size.

Comments (0)

No comments at this moment