Best fit
RAID-Z1
Smaller ZFS pools where one-drive tolerance and capacity efficiency match the stated risk boundary.
- • Single parity.
- • Vdev shape affects future growth.
- • Snapshots do not create an independent backup.
ZFS choice
RAID-Z1 or RAID-Z2?
Choose a ZFS vdev layout by capacity, fault tolerance, future pool design, and the backup plan outside the pool.
Best fit
RAID-Z2
Users accepting the capacity cost of two-drive tolerance for a more conservative pool baseline.
- • Dual parity uses more raw capacity.
- • Needs enough bays to be a useful fit.
- • Pool design should be decided before the drive purchase.
Decision rule
Decide the vdev shape before buying drives. Compare both layouts against data importance, recovery copies, planned bay count, and how the pool will grow.
Editorial record
Maintained by Make Your Own Tools to turn “Store data safely” into a defined capacity, bays, redundancy, and recovery baseline. The references below provide the technical context for this planning path. Its calculation rules and planning assumptions are documented in the methodology, and affected calculations pass regression checks before the review date advances.
- Last reviewed
- Evidence set
- 2 primary references
- Planning scope
- ZFS vdev capacity and protection planning.
- Next check
- A complete TrueNAS deployment design.