HostRAID is an integrated RAID technology that adds entry level RAID support. It is also called intelligent RAID on chip (iROC) or software RAID and it is built into the firmware of the controller. There is no additional RAID processor on HostRAID cards.

With the listed SAS and SATA HostRAID controllers, HostRAID is always enabled by default. There are only HostRAID drivers available, regardless if the drives are configured as RAID or if they are being used in JBOD mode.

With the listed Ultra320 SCSI controller cards, this feature needs to be enabled in the BIOS. By default HostRAID is disabled. Please keep in mind there are different driver files necessary dependent on the HostRAID setting. If HostRAID is disabled, the SCSI driver needs to be installed. If HostRAID is enabled, the HostRAID driver needs to be installed. Please see the User's Guide for further details on how to enable or disable HostRAID and on how to migrate SCSI to HostRAID or vice versa.

Please see Answer ID 8986 for the limitations that apply to HostRAID.