User`s guide

Note
HSJ30 and HSJ40 array controllers hereafter are referred to as HSJ
array controllers unless the text is controller-model specific.
HSZ40–Ax and HSZ40–Bx array controllers hereafter are referred to as
HSZ array controllers unless the text is controller-model specific.
1.2 Housing for HS Array Controllers
The controller modules and associated read and write-back cache modules mount
in a controller shelf.
1
Each controller shelf supports up to two controller modules,
two read or write-back cache modules, and one or two shelf power supplies.
The controller shelf slides into slots in StorageWorks cabinets. The same array
cabinets contain storage shelves that hold the storage devices supported by the
controllers.
The SCSI–2 device cables (also known as port or bus cables) are connected to
the controller shelf backplane, routed out the front of the controller shelf, and
routed into the front of storage shelves (such as the BA350–SB shelf) that hold
the SCSI–2 devices.
At the lowest level, a SCSI–2 device fits into a plastic carrier. The combination
of the plastic carrier and the storage device is called a StorageWorks building
block (SBB). These SBB carriers slide into slots in the storage shelves.
1.3 Physical Description of HS Array Controllers
The following sections describe the physical attributes of each HS array controller
model including HSJ (both HSJ30 and HSJ40 array controllers), HSD30, and
HSZ (HSZ40–Ax and HSZ40–Bx array controllers).
1.3.1 HSJ30 and HSJ40 Array Controllers Physical Description
The physical HSJ40 array controller module has three SCSI–2 shelf backplane
connectors with the following features:
• Each shelf backplane connector supports two SCSI–2 ports for a total of six
SCSI–2 ports (buses) for the HSJ40 controller.
The HSJ30 array controller supports three SCSI–2 ports. The command line
interpreter does not allow any configurations past port 3 to be entered for
HSJ30 controllers (devices on ports 4, 5, and 6 are ignored).
• Each SCSI–2 port supports up to six (or seven) SCSI–2 devices,
2
, depending
on the subsystem configuration.
Note
The HSJ30 controller supports up to 18 devices in a dual-redundant
configuration. Lower availability configurations can support up to 21
devices (seven per SCSI–2 port) if nonredundant power is not used. Other
1
Controllers and their cache modules can reside in either a BA350–MA controller shelf or
a SW300-series cabinet shelf.
2
An HSJ40 dual-redundant controller configuration supports up to 36 devices. Lower
availability configurations can support up to 42 devices (seven per SCSI–2 port) but this
will sacrifice a convenient upgrade to any of the possible higher availability options, such
as redundant power. For this reason, Digital does not recommend this configuration.
1–2 Introduction to HS Array Controllers