User`s guide

The point of these examples is to show that arbitrary DEC OSF/1 device names
cannot be chosen if MAKEDEV is used to create the special files. The minor
number that MAKEDEV will calculate must identify the correct HSZ40 Unit on
the correct host side SCSI bus.
8.15 Helpful Utilities
The DEC OSF/1 file utility can be used to determine if an HSZ40 unit can be
accessed from the DEC OSF/1 host operating system.
For this example, the HSZ40 has a unit designator of D101. From the HSZ40
CLI enter the following command:
HSZ> Set D101 noread
This command disables the read cache for the unit. This allows for a visual
indication that the unit is being accessed. The information should be accessed
from the unit rather than from the cache (if the information is in cache).
Make sure that the unit’s read cache is reenabled when the testing is completed
by entering the following command:
HSZ> Set D101 read
If an HSZ40 unit has write-back cache enabled, first the write-back cache for the
unit must be disabled, then the read cache is disabled:
HSZ> Set D101 nowriteback
HSZ> Set D101 noread
Make sure that the unit’s write-back and read cache are reenabled when the
testing is complete.
From the DEC OSF/1 host operating system console enter the following command:
/usr/bin/file /dev/xxxx
The xxxx represents the DEC OSF/1 Character Mode device special file that
represents a partition on the HSZ40 unit, for example:
/usr/bin/file /dev/rrzb17a
In this example, the special file for rrzb17a should already be created. Also, the
partition that is chosen should have the correct disk label.
8–38 Operating System Support