- ATTO FibreBridge Installation & Operations Manual

ATTO Technology, Inc. ATTO FibreBridge Installation & Operation Manual
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ATTO Technology, Inc.
For best performance, keep SCSI cabling distances as short as possible.
A FibreBridge with an LVD SCSI personality module is downward compatible with Single Ended Ultra
SCSI as well as Fast, Wide, or Narrow SCSI devices. The entire SCSI bus will operate at the speed of the
slowest device. If you wish to mix devices of different SCSI speeds on the bridge, it is best to separate
them. That is, put the slower devices on bridge SCSI bus 1, and the faster devices on bridge SCSI bus 2.
Each bus is independent so each can operate at a different speed.
The high voltage differential bridge is only compatible with HVD SCSI devices.
For maximum performance, it is possible to stripe devices across both SCSI busses. ATTO’s
ExpressRAID software for PC or MAC can be used to create RAID 0 groups consisting of drives attached
to both SCSI busses. For example, four Ultra SCSI drives striped together on bridge bus 0 will reach a
performance limit of near 40 MB/sec (the Ultra SCSI limit). Four Ultra SCSI drives on bridge bus 1 striped
with four drives on bridge bus 2 will sustain nearly 80 MB/sec. ATTO’s ExpressRAID also makes it
possible to stripe multiple hardware RAID controllers together.
Figure 6.1 Typical SCSI Cables
SCSI Termination