Setting Up The Scsi Bus; Scsi Id Numbers; Identifying Scsi Ids - HP 330834-B21 - StorageWorks Ultrium 460 Tape Library Drive Module User Manual

• The voltage level of the interface, which may be single-ended (SE) or low voltage differential (LVD).

Setting up the SCSI bus

Each device on a SCSI bus, including the SCSI host bus adapter (HBA), must be configured with a unique
ID (identifier). The SCSI bus must be terminated.
NOTE:
HP recommends that a dedicated host bus adapter is used for the tape drive. A suitable adapter is
available from HP as an accessory (see http://www.hp.com/go/connect.

SCSI ID numbers

For wide SCSI buses, the SCSI ID will be a number from 0 through 15, so a typical wide SCSI HBA can
accommodate up to fifteen other devices. (On narrow SCSI buses, the SCSI ID is a number from 0
through 7.)
Each device must have a unique SCSI ID. The drive can be assigned any unused ID between 0 and 15.
Do not use SCSI ID 7, which is reserved for the SCSI controller. SCSI ID 0 is typically assigned to the boot
disk and should also not be used unless the tape drive is on a dedicated SCSI bus.
SCSI ID 7 is normally reserved for the HBA because it has the highest priority on the bus. On wide buses,
the priority runs from 7 (highest) to 0, then 15 down to 8 (lowest).
NOTE:
As a general rule, avoid putting tape devices on the same bus as any hard disks.

Identifying SCSI IDs

If your computer already has devices connected to the SCSI bus, you will need to know their IDs to avoid
any conflict with the new tape drive. Here are some methods of finding out the information:
• The fastest and easiest way is to run HP Library & Tape Tools from the HP StorageWorks CD-ROM.
HP Library & Tape Tools will check your SCSI configuration, including the SCSI controller itself
and any devices currently attached to it.
• Most computers display a list of SCSI devices and IDs during the boot-up process. This usually
scrolls past very fast. If you press the [Pause] key, you should be able to halt the scrolling and
view the list.
• On Windows systems, you can use Device Manager.
• If you have Novell NetWare installed, use its LIST DEVICES command.
If none of these is available to you, try the following sources of information:
• The details of all installed devices and settings may have been written down and stored with your
computer's documentation (for new computers, this is often done by the supplier).
• Your HBA's documentation should tell you which settings it uses.
• Look at each device to find out its ID. This is usually easy with external devices. With internal
devices, you will probably need the help of the device's documentation to identify the SCSI
ID setting, which is usually set with jumpers.
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SCSI configuration guide