Recovery
Use RAID for availability, not as the only backup
Plan the primary NAS and recovery copies as different jobs. The backup has to be reachable when the primary array is not.
Decision 01
Name the failure boundary
Drive failure, accidental deletion, malware, hardware failure, and site loss are different events. A storage plan is complete only when each important data set has a recovery path.
Decision 02
Keep copies independent
An external drive, second NAS, or remote destination can be independent. The exact choice depends on data size, restore time, and location risk.
Decision 03
Test a representative restore
Choose a file set, document the steps, perform the restore, and record the result. A green backup job is not the same as a usable recovery.