Why is the scsi bus type important, How can i check the scsi bus type and scsi id, Power specifications – HP StoreEver Ultrium Tape Drives User Manual
Page 15: 2 supported scsi bus types
Why is the SCSI bus type important?
The SCSI bus type determines the speed at which data can be transferred between devices on the bus
and the maximum length of cable that can be used. Ultrium 1760 and 920 drives support a burst transfer
rate of 320 MB/sec. Ultrium 448 and 232 drives support a burst transfer rate of 160 MB/sec. To benefit
from this level of performance, it is important to ensure that the drives are connected to a SCSI bus of a
similar or higher specification. This means that you need:
•
An Ultra320 bus for Ultrium 1760 and 920 drives. An Ultra160 or Ultra320 SCSI bus for Ultrium
448 and 232 drives. If you attach the drive to a lower specification SCSI bus, it may still work but
data will not be transferred as quickly.
•
LVD-rated SCSI cabling and terminators. The LVD interface enables the data to be transferred at
the drive’s maximum rate.
Table 2 Supported SCSI bus types
SCSI Bus Type
Supported
Ultra320 LVD
Yes. This is a recommended configuration for all Ultrium tape drives.
Do not daisy chain Ultrium 1760 or Ultrium 920 tape drives because performance
may be degraded. Do not daisy chain Ultrium 448 and Ultrium 232 tape drives
with Ultra320 devices.
Ultra160 LVD
Yes. This is a recommended configuration for Ultrium 448 and 232 tape drives. It is
an acceptable configuration for Ultrium 1760 and Ultrium 920 tape drives, but it
could limit performance on the Ultrium 1760 tape drive.
Up to two Ultrium 448 and 232 tape drives may be daisy-chained. Do not
daisy-chain Ultrium 1760 or Ultrium 920 tape drives.
Ultra2 LVD
Yes. This is acceptable for one Ultrium 448 drive per bus or two Ultrium 232 drives
per bus.
Do not use with Ultrium 1760 or Ultrium 920 tape drives and do not daisy-chain
Ultrium 448 tape drives.
Ultra wide
LVD and
single-ended
These are not recommended configurations because they will restrict performance.
Ultra narrow,
single-ended
No. This will severely restrict performance and you will need a suitable cable or
adapter.
High Voltage
Differential
No. The drive will not work and you may damage the drive or controller.
How can I check the SCSI bus type and SCSI ID?
For many operating systems, you can install and run HP Library & Tape Tools from either the
HP StorageWorks Tape CD-ROM or
k your server’s
current SCSI configuration (see also “
” on page 57). This will provide information about
the SCSI bus and the SCSI IDs in use.
Power specifications
For a detailed product specification, please refer to our World Wide Web site (
Ultrium Half-Height SCSI Tape Drives
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