Storage Tiering
TrueNAS Enterprise
This feature is only available on TrueNAS Enterprise systems.
Storage Tiering is an Enterprise feature that operates as a share-level toggle that lets admin users decide whether to write data to flash performance tiers or regular HDD tiers within a fusion pool at any time.
What is a Fusion Pool?
A fusion pool is a hybrid storage pool that mixes slow, high-capacity spinning hard drives (HDDs) and fast, low-latency solid-state drives (SSDs or NVMes) within a single ZFS storage pool to improve performance. Fusion pools are also known as ZFS allocation classes, ZFS special vdevs, and metadata vdevs (Metadata vdev type on the Pool Manager screen).
Storage Tiering Pool Migration
Storage Tiering is only available on TrueNAS Enterprise systems.
This tutorial covers using the ZFS storage tiering feature introduced in TrueNAS 26 to migrate a TrueNAS Enterprise storage appliance from a two-pool configuration (for example, an HDD pool with a mirrored special vdev and a separate SSD pool) to a single tiered pool.