User`s guide

Example 8–8 (Cont.) SCSI Bus Number Determination
NOTICE: An external SCSI Host Adapter named PZA0
resides at PCI slot 7. It is attached to SCSI bus
number 2 (SCSI--2). A disk with a name of
rz18 is accessed over this bus through an HSZ40
controller. This information is obtained from the
previous error log entry:
pza0 at pci0 slot 7
scsi2 at pza0
rz18 at scsi2 bus 2 target 2 lun 0
_(DEC HSZ40 (C) DEC V20Z)
The information from the error log entry shows that the auto-config routines
in the DEC OSF/1 system startup can access the unit. However, this does
not necessarily mean that the users of this system will be able to access the
HSZ40 unit. The device special files that associate an HSZ40 unit with a DEC
OSF/1 device name may not have been created or they may have been created
incorrectly.
To see a unit on an HSZ40 controller from the Startup procedures, the device
name information must be in the DEC OSF/1 Configuration File. Also, for DEC
OSF/1 versions up to and including V3.2-4 the name must be in the following
format:
rznn
where nn are numeric characters.
The following is an example from a configuration file:
disk device rz18 at scsi2 drive N
where: rz18 is the DEC OSF/1 device name.
N represents a drive number and is determined from the following components:
• Host SCSI bus number
• HSZ40 unit designator
The following formula is used to determine the drive number:
( 64 * Host Side Bus # ) + ( 8 * Target ID ) + LUN
The drive number is the entity that allows the DEC OSF/1 startup procedures to
identify the device.
The Target ID and LUN are determined from the HSZ40 unit designator.
Note
The device name does not necessarily have to be in the format rznn.
However, some utilities may not recognize the DEC OSF/1 device name if
this numeric format is not used, including the startup procedures.
Operating System Support 8–29