Platform choice

RAID 6 or RAID-Z2?

Both are dual-parity planning models, but platform behavior, pool design, expansion, and operations determine which path fits.

Best fit

RAID 6

Users selecting a platform with conventional dual-parity RAID and an expansion path they have verified.

  • • Capacity math alone does not describe controller or platform behavior.
  • • Verify migration, rebuild, monitoring, and compatibility rules.

Best fit

RAID-Z2

ZFS users designing vdev shape, snapshots, scrubs, replication, and future pool growth together.

  • • Vdev design should be decided before drive purchase.
  • • ZFS features improve integrity and recovery workflow but do not remove backup requirements.

Decision rule

Do not choose between these labels on usable TB alone. Start with the platform you can operate, then verify its expansion and recovery model for the full lifecycle of the pool.

Build the baseline first

Sources and scope

Last reviewed 2026-07-13. This page separates the decision it supports from the facts that still require a platform or model-specific check.

Applies to

Dual-parity planning before selecting a platform.

Does not cover

Feature parity between operating systems or appliances.

TrueNAS ZFS Capacity CalculatorZFS capacity, redundancy, and configuration-planning reference.Open source ↗Synology RAID CalculatorCapacity estimation for supported Synology drive combinations.Open source ↗