RAID is not a replacement for backups; they do different things.<p>RAID preserves performance and&#x2F;or uptime in the face of hardware failures. It does not protect against data corruption or deletion. It will happily sync those across all your disks.<p>Backups protect against any data loss: hardware, software, even intentional. The key feature of a backup is that it is insulated from live data operations (including RAID sync).