NAS pSEO Landing
Estimate usable TB, parity overhead, and fault tolerance for 5x 6TB in RAID 5. Includes reserve planning for NAS and homelab arrays.
Raw Capacity
30.00 TB
Usable Capacity
21.60 TB
Fault Tolerance
1 drive
Efficiency
80.0%
Balanced capacity and redundancy, but rebuild stress can be high on large disks. This scenario applies a 10% filesystem reserve.
Run Interactive Calculator →| Mode | Usable | Tolerance | Efficiency |
|---|---|---|---|
| RAID 5 | 21.60 TB | 1 drive | 80.0% |
| RAID 6 | 16.20 TB | 2 drives | 60.0% |
| RAID 10 | N/A | N/A | N/A |
| RAID-Z1 | 21.60 TB | 1 drive | 80.0% |
| RAID-Z2 | 16.20 TB | 2 drives | 60.0% |
Keeping free space improves filesystem behavior for snapshots, metadata, and write performance. Full arrays often perform worse and rebuild more slowly.
It can be practical, but larger drives increase rebuild windows. Validate parity choice and backup policy before committing to the final layout.
This setup can tolerate 1 drive. Real-world survivability depends on mirror placement, rebuild stress, and drive health.
This NAS planning scenario estimates 21.60 TB usable after a 10% reserve from 30.00 TB raw.