RAID is not sufficient for backup - sudo-arshia/tips_and_tricks GitHub Wiki

RAID is primarily designed for improving performance and providing fault tolerance within a storage system. While RAID can offer some level of redundancy and protection against disk failures, it is not a substitute for a proper backup solution.

Here are a few reasons why RAID alone is not sufficient for backup:

  1. Data Corruption and Accidental Deletions: RAID does not protect against data corruption or accidental deletions. Any corruption or deletion that occurs on one disk will be mirrored or distributed across all disks in the RAID array, potentially resulting in the loss of data on all disks.

  2. Hardware Failures and Disasters: RAID protects against individual disk failures but does not provide protection in case of larger-scale hardware failures or disasters, such as power surges, fires, floods, or theft. These events can render the entire RAID array unusable and result in data loss.

  3. Malware and Ransomware Attacks: RAID does not protect against malware or ransomware attacks that may encrypt or destroy data on all disks in the array. If the RAID array is the only copy of the data, it may be impossible to recover the original data without a separate backup.

  4. Human Errors and File System Corruption: RAID does not protect against human errors, such as accidental file deletions or formatting of the entire array. Additionally, RAID does not provide protection against file system corruption, which can occur due to software or operating system issues.

  5. Long-Term Data Retention: RAID does not address the need for long-term data retention. If data needs to be retained for extended periods, such as for compliance or legal reasons, a backup solution with appropriate retention policies is necessary.

Therefore, while RAID can provide some level of redundancy and protection against disk failures, it is strongly recommended to implement a separate backup solution alongside RAID. A backup strategy involving regular backups to separate storage media, preferably offsite or in the cloud, ensures that data can be recovered in case of any unforeseen events or data loss scenarios.