Connecting External Scsi Devices - Sun Microsystems Ultra Enterprise 3000 System Installation Manual

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2.7 Connecting External SCSI Devices

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External SCSI-2 devices connect to your system through the built-in single-
ended Fast/Wide SCSI-2 port on I/O boards (except for the board in slot 1), or
through FSBE/S, DSBE/S, SWIS/S, or DWIS/S SBus cards installed on I/O
boards.
Note – The onboard SCSI-2 bus on the I/O board in slot 1 controls internal
SCSI tray devices. Therefore, the external SCSI connector on the I/O board in
slot 1 must always have a terminator installed.
Note – The maximum combined length for a string of SCSI cables is six meters
for non-differential cables. For differential SCSI cables, the maximum is 25
meters.
When calculating the total length of a SCSI string, include external cables,
internal cables, and printed traces. Table 2-2 lists internal measurements for the
Enterprise servers.
Table 2-2 Internal SCSI Lengths (Approximate)
Location
SBus I/O board
Graphics I/O board
For information on device addressing, priorities, and slot assignments, refer to
Appendix D, "Rules for System Configuration" in the Ultra Enterprise 3000
System Manual, p/n 802-6051.
Caution – Risk of equipment damage. Do not assign the same SCSI address to
two devices sharing the same SCSI bus or SBus card.
To connect an external SCSI device to your system:
1. Connect a SCSI cable to the appropriate SCSI-2 host on the I/O board.
• For the I/O board in slot 1, this is an SBus card installed in an appropriate
SBus slot.
Ultra Enterprise 3000 System Installation Guide—May 1996
Internal Length
0.43 meter
0.43 meter