Host Bus Adapters

When using a Host Bus Adapter (HBA) in a system that relies on software-managed redundancy, such as a NAS or server running ZFS, it is highly recommended that the HBA be flashed to IT Mode (Initiator Target mode). This mode disables any hardware RAID functionality and ensures that the operating system has direct, unaltered access to each individual drive. This is crucial for ZFS, which handles redundancy, integrity checking, and data repair entirely in software. If the HBA abstracts or modifies drive behavior, it can interfere with ZFS's ability to detect and correct data corruption, undermining the reliability of the entire storage pool. By using IT Mode, the system gains full visibility and control over every disk, enabling ZFS to manage its advanced features, such as checksumming, copy-on-write, RAID-Z, and self-healing capabilities, without interference. This setup is ideal for platforms like TrueNAS, Proxmox, or Linux servers where ZFS is used for robust, fault-tolerant storage.

8 Internal Drive Controllers

Generation	Model	Controller	PCIe Interface	SAS Speed	Idle Power	Load Power	IOPS
2nd Gen	9211-8i	SAS2008	PCIe 2.0 x8	SAS2 6 Gb/s	7w	8w	≥ 320K
3rd Gen	9207-8i	SAS2308	PCIe 3.0 x8	SAS2 6 Gb/s	9w	10w	≥ 650K
4th Gen	9300-8i	SAS3008	PCIe 3.0 x8	SAS3 12 Gb/s	11w	12w	≥ 1000K
6th Gen	9400-8i	SAS3408	PCIe 4.0 x8	SAS3 12 Gb/s	6w	7w	≥ 1.5M
7th Gen	9500-8i	SAS3808	PCIe 4.0 x8	SAS3 12 Gb/s	4w	6w	≥ 3M

16 Internal Drive Controllers

Generation	Model	Controller	PCIe Interface	SAS Speed	Idle Power	Load Power	IOPS
2nd Gen	9201-16i	SAS2116	PCIe 2.0 x8	SAS2 6 Gb/s	13w	15w	≥ 430K
4th Gen	9300-16i	dual SAS3008 with PLX	PCIe 3.0 x8	SAS2 12 Gb/s	24w	25w	≥ 2M
5th Gen	9305-16i	SAS3224	PCIe 3.0 x8	SAS3 12 Gb/s	13w	14w	≥ 1.5M
6th Gen	9400-16i	SAS3416	PCIe 3.0 x8	SAS3 12 Gb/s	8w	9w	≥ 1.5M
7th Gen	9500-16i	SAS3816	PCIe 4.0 x8	SAS3 12 Gb/s	6w	8w	≥ 3M