User`s guide

However, the host side SCSI host adapter’s SCSI ID is also on this bus. The
HSZ40 array controller’s host side SCSI IDs must be different than the host
adapter’s ID. Usually the host adapter’s ID is 7. However, this ID is usually
configured through the host system console utilities and it can be something
other than 7. It is recommended that the host adapter use ID 7.
The HSZ40 array controller’s host side IDs are set using the HSZ40 array
controller’s Command Language Interpreter (CLI). The CLI is accessed
through the maintenance terminal port on the front bezel of the HSZ40 array
controller.
The HSZ40 array uses device side SCSI IDs of 7 or 6. These IDs are
dependent upon the physical slots of the controller shelf in which the HSZ40
array controller is installed.
If the HSZ40 array controller is located in the slot furthest from the device
side SCSI connectors, its device side ID is 7. If the HSZ40 array controller
is located in the physical slot closest to the device side SCSI connectors, its
device side ID is 6. In a dual-redundant controller configuration, one HSZ40
array controller has a device side ID of 7, the other controller has a device
side ID of 6. In a single HSZ controller configuration, the controller should
always be mounted in device side ID slot 7.
• HSZ40 Storage Container—Is a single- or multiple-device storageset.
• HSZ40 UNIT—This entity represents a storage container that is available for
use by the DEC OSF/1 host operating system. HSZ40 units are created from
storage containers. Until a storage container is made into a unit, the storage
container is not available to the DEC OSF/1 operating system.
• HSZ40 UNIT Designator—This entity is used by the HSZ40 to identify a
unique storage container that is made available to the host operating system.
The unit designator is assigned to a storage container when the storage
container is configured as a unit, by the CLI’s ADD UNIT command.
The unit designator consists of a host side SCSI ID and a host side LUN.
• DEC OSF/1 Disk Device—(As used in reference to an HSZ40 array
controller subsystem.) A DEC OSF/1 disk device is a DEC OSF/1 entity
that relates to an HSZ40 unit. A DEC OSF/1 disk device can be a single
disk device container or a multidisk device container, depending upon the
configuration of the HSZ40 unit that relates to the OSF/1 disk device.
The relationship between the HSZ40 unit and the DEC OSF/1 disk device
name is made by invoking the DEC OSF/1 utility, mknod.
• SCSI Target ID—Unfortunately, the term Target ID as used in an HSZ40
controller environment refers to two different entities. There is a Target ID
as used on the Host Side bus, and another Target ID as used on the device
side bus.
Host Side Target ID—This is one of the four SCSI ID numbers assigned to the
host side SCSI ID. This Target ID is used by the host adapter to communicate
with the HSZ40 array controller.
Device Side Target ID—This SCSI ID is used to communicate between the
HSZ40 array controller and the devices on the Device Side SCSI buses. It is
used by the HSZ40 controller to identify a unique device on one of the device
side SCSI buses. From a user’s point of view, the device side target ID is only
used when configuring devices on the HSZ40 array controller.
Operating System Support 8–27