Why include a 10% reserve when planning NAS storage headroom?
Keeping free space improves filesystem behavior for snapshots, metadata, and write performance. Full arrays often perform worse and rebuild more slowly.
Should I optimize this 4-drive plan for available space or resiliency first?
For long-lived NAS pools, resiliency first is usually safer. Capacity can be expanded later, while a risky parity choice can force migration sooner.
How many disk failures can RAID 5 tolerate in this setup?
This setup can tolerate 1 drive. Real-world survivability depends on mirror placement, rebuild stress, and drive health.
Can this calculator replace real-world benchmark and rebuild testing?
No. Use this page for pre-purchase sizing, then validate with workload benchmarks, SMART health policy, and a tested restore plan.