The Future Domain SCSI host adapter driver enables SDI-compliant target drivers (such as sd01 and st01) to communicate on the SCSI bus with target controllers and logical units. This allows normal access to mass-storage devices using standard system interfaces and filesystems.
It is also possible for a knowledgeable user to access the SCSI bus subsystem directly by using the driver's pass-through interface. This allows the user to issue sb control blocks directly to a SCSI target device. To find the appropriate pass-through device to use for a particular target device, the user should open(2) the character special file for the device in question and then issue the B_GETDEV ioctl. The device value returned should then be used to create a character special file which, when opened, can be used for pass-through (SDI_SEND) ioctl.
With Future Domain controllers (for example, TMC-850M, TMC-1680, and TMC-3260), the SCSI boot disk must be the disk with the highest SCSI target address (SCSI ID). For example, if you have disks at SCSI IDs 3, 4 and 6, the boot disk must be the disk at SCSI ID 6. If you attempt to boot from a SCSI disk which is not the highest ID, it might not work. Because Future Domain controllers do not consider removable-media disks as bootable, attempting to boot from such a disk might fail.