NAS pSEO Landing
Brand Focus · TrueNAS
Estimate usable TB, parity, and fault tolerance for TrueNAS NAS users using 6x 16TB in RAID 6.
Raw Capacity
96.00 TB
Usable Capacity
57.60 TB
Fault Tolerance
2 drives
Efficiency
66.7%
Safer for larger arrays with dual parity, at the cost of one extra parity disk. This scenario applies a 10% filesystem reserve.
Run Interactive Calculator →| Mode | Usable | Tolerance | Efficiency |
|---|---|---|---|
| RAID 5 | 72.00 TB | 1 drive | 83.3% |
| RAID 6 | 57.60 TB | 2 drives | 66.7% |
| RAID 10 | 43.20 TB | 1 drive per mirror pair* | 50.0% |
| RAID-Z1 | 72.00 TB | 1 drive | 83.3% |
| RAID-Z2 | 57.60 TB | 2 drives | 66.7% |
TrueNAS and ZFS planners usually care about parity width, scrub cadence, and healthy operating headroom. Capacity is only one part of pool durability.
A virtual device group in ZFS; multiple vdevs form a storage pool.
Background integrity scan that verifies checksums and repairs parity mismatches.
ZFS feature set and planning topic for growing parity groups safely.
For TrueNAS users, this NAS planning scenario estimates 57.60 TB usable after a 10% reserve from 96.00 TB raw.
For long-lived NAS pools, resiliency first is usually safer. Capacity can be expanded later, while a risky parity choice can force migration sooner.
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 2 drives. Real-world survivability depends on mirror placement, rebuild stress, and drive health.