Additional Scsi Buses - Sun Microsystems 2.1 Gbyte 7200 rpm Installation Manual

• 0.8 meters (for the Desktop Storage Module cable)
• 0.3 meters (for the internal circuitry of the Desktop Storage Module)
The total length of cable for this configuration is 2.7 meters of cable, less
than the 6 meter maximum for each SCSI bus.

Additional SCSI Buses

If the SCSI bus length exceeds 6 meters, you can install some of the devices on
additional SCSI buses by installing an SBus SCSI Host Adapter card (SSHA) or
a FSBE/S with desktop systems or an SBE/S SBus card with deskside systems.
The SBus SCSI Host Adapter card provides an additional SCSI port (SCSI bus)
for your system. The SBE/S or FSBE/S SBus card provides an additional SCSI
port and an Ethernet port.
When you insert an SBus SCSI Host Adapter card into your system, the SCSI
bus length total does not include the internal cable length of the system, listed
in Table B-2. For example, if you have a SPARCstation IPC and are connecting
two Desktop Storage Modules and two DDPs to the SBus SCSI Host Adapter
card of the system, you need to add the following cable lengths:
•
3.2 meters (4 SCSI cables, 0.8 meters x 4 cables)
•
0.8 meters (2 DSMs, 0.4 meters x 2 units)
•
0.6 meters (2 DDPs, 0.3 meters x 2 units)
•
0.1 meters (SBus SCSI Interface FSBE/SSHA/SBE)
The total length of cable for this configuration is 4.5 meters of cable length, less
than the 6 meter maximum for each SCSI bus. Note that you do not include the
internal bus length of the SPARCstation IPC (0.5 meters).
Additional SCSI buses, SCSI bus 1, 2, 3, and 4 are named based on the order
they are found by the OpenBoot™ PROM when probing SBus slots. SBus slots
are probed in this order: on-board, slot 0, slot 1, slot 2, slot 3.
For example, if the first FSBE/S SBus card is in slot 2, when the system probes
the SBus slots, it begins probing the on-board SCSI bus, then SBus slot 1, then
SBus slot 2, and so on. Because slot 2 contains the first FSBE/S SBus card, this
is SCSI bus 1. As Table B-2 illustrates, SCSI bus 1 supports disk, tape, and
CD-ROM.
Small Computer Systems Interface Information
B
B-5