# Decoding the 3-2-1-1-0 Backup Strategy​ https://forums.truenas.com/t/explaining-the-3-2-1-1-0-backup-method-simplifying-data-protection-with-truenas/648 While RAID (Redundant Array of Independent Disks) improves **availability** by minimizing downtime due to drive failure, it doesn’t offer the **redundancy** and **protection** against data loss that a backup system provides. The 3-2-1-1-0 backup strategy serves as a blueprint for comprehensive data protection, emphasizing redundancy and accessibility. Let’s break it down: **3 Copies:** To start, the strategy calls for maintaining three copies of your data; the original data, plus two additional copies. This redundancy ensures that if one copy or even two are compromised, at least one remains intact, minimizing the risk of irretrievable loss. **2 Different Types of Media:** Storing copies on two different types of media helps keep your data available in the event one of the media suffers a physical or logical failure. For example, a high-performance all-flash system stores the primary copy of your data for the fastest production performance, and a second system using lower cost hard drives is used to store a local backup or replica copy. **1 Copy Offsite:** Having at least one copy stored offsite ("air-gapped") safeguards against localized disasters like fire, theft, or natural calamities. Cloud storage services ([like iX-Storj built into TrueNAS 40](https://www.truenas.com/ix-storj/)) offer a convenient offsite option to ensure data accessibility even in the face of catastrophic events. **1 Copy Offline:** Historically, this meant an air-gapped copy that is isolated from any network, making it impossible for a bad actor or anyone to tamper with it. “Immutable,” or unchanging over time, is a feature today’s users are interested in to protect from bad actor cyber threats like ransomware. By maintaining one such copy, organizations can retain confidence in their ability to recover from malicious events. **0 Errors:** Regularly verifying backups for errors and practicing recovery is vital to ensure any backup strategy will work if/when the time comes to recover. Any backup strategy is only as effective as its ability to restore data accurately. [[TrueNAS SCALE]], the newest version of TrueNAS, epitomizes simplicity and efficiency in data management, including backups. --- According to Immich: > A [3-2-1 backup strategy](https://www.backblaze.com/blog/the-3-2-1-backup-strategy/) is recommended to protect your data. You should keep copies of your uploaded photos/videos as well as the Immich database for a comprehensive backup solution. > > A 3-2-1 backup includes: > > 3 total copies of your data, including the original files. This includes 1 offsite copy and 2 local copies. > > 2 local copies on different devices. This includes the main files and a backup of those files locally. > > 1 offsite copy in the cloud or at another physical location. > > For more information about backing up Immich, please refer to the [documentation](https://immich.app/docs/administration/backup-and-restore/).