mscsi -- SCSI peripheral device configuration file


ha attach number ID lun [ bus ]


The mscsi file (/etc/conf/cf.d/mscsi) is a description of each SCSI peripheral device connected to a SCSI host adapter. Peripheral devices and host adapters are configured statically in the kernel by the Link Kit using this file.

Each line in mscsi represents one SCSI device connected to a host adapter, and contains five fields separated by spaces or tabs. Comment lines are begun with an asterisk ``*''.

Each field described below must be supplied with a value:

The name of the host adapter driver being used. This name corresponds to field 1 (xnamex) in the mdevice(F) file (not necessarily the same as the driver handler prefix).

The auto keyword indicates a non-configured host adapter. Such an adapter can use one of several host adapter drivers (if these are already linked into the kernel) or an adapter driver loaded at boot time.

There can be at most one non-configured host adapter in a system. There may be several auto lines, but each line must correspond to a different permitted peripheral driver specified by the attach field.

The version of mscsi used in the install kernel includes auto lines for hard disk, tape, and CD-ROM devices only.

The name of the peripheral driver that controls the device. Possible values are:

hard disk drive

floppy disk drive

CD-ROM drive

tape drive

The host adapter number distinguishes different host adapters controlled by a single adapter driver. The first adapter controlled by a given driver is numbered as 0 (zero), the second as 1, and so on (see ``Examples'' below). A non-configured host adapter (ha field set to auto) always has number set to 0.

The unique identification number of a controller on the SCSI data bus. Up to eight controllers may be present on an 8-bit wide data bus with IDs from 0-7. Sixteen controllers may be present on a 16-bit wide data bus with IDs from 0-15. Note that the host adapter is typically assigned ID 7; if it assigned a higher number, SCSI devices that use 8-bit addresses on a 16-bit wide data bus will be unable to see it.

The SCSI logical unit number (LUN) of the peripheral device. Bridge controllers can support up to eight SCSI devices with LUNs in the range 0-7. Most SCSI devices, however, contain an embedded controller and a LUN of 0.

The number of the SCSI bus on the the host adapter, and to which the target device is attached. Many host adapters control only a single bus; in this case, this field should be set to 0. Host adapters, such as the Adaptec 2742T, can control two buses; this field is then set to 0 for the first/primary bus, and 1 for the second/secondary bus. If omitted, this field is assumed to be set to 0.


A mscsi file for a system with a single Adaptec 154x host adapter, one SCSI tape drive and two disks:
   *ha  attach  number  ID  lun  bus
   ad   Stp     0       2   0    0
   ad   Sdsk    0       0   0    0
   ad   Sdsk    0       1   0    0
An example mscsi file for a system with one twin bus Adaptec 2742T, and two NEC DPT PM2012 host adapters:
   *ha  attach  number  ID  lun  bus
   dpt  Stp     0       2   0    0
   dpt  Sdsk    0       0   0    0
   dpt  Sdsk    1       0   0    0
   dpt  Sdsk    1       5   0    0
   arad Sdsk    0       0   0    0
   arad Sdsk    0       0   0    1
Note that number for the Adaptec host adapter is 0 because it is the first instance of that adapter type. Two SCSI disks, each with controller ID 0, are attached to the Adaptec's primary (bus 0) and secondary (bus 1) buses.

The following mscsi file allows for a non-configured host adapter that chooses its driver automatically. This example uses the maximum number of peripherals available to a non-configured host adapter (one per peripheral driver type):

   *ha  attach  number  ID  lun  bus
   auto Sdsk    0       0   0    0
   auto Stp     0       2   0    0
   auto Srom    0       1   0    0
   auto Sflp    0       4   0    0


full pathname of mscsi

See also

cdrom(HW), hd(HW), mkdev(ADM), scsi(HW), scsitape(HW), Sflp(HW), tape(HW)
© 2003 Caldera International, Inc. All rights reserved.
SCO OpenServer Release 5.0.7 -- 11 February 2003