Compaq AA-RHGWC-TE - Manual (Page 286)

When the expansion unit comes up, it will communicate with each base and
data unit through the expansion unit interface and inventory the number
of base units, tape drives, data units, and cartridges present in each base
and data unit. After the MiniLibrary configuration has been determined, the
expansion unit will communicate with each base and data unit and indicate
to the modules which cartridge group that base or data unit contains.
When all initialization communication between the expansion module and
each base and data unit has completed, the base and data units will display
their cartridge numbers according to the remapped cartridge inventory.
8.12.2.2.4 Setting the SCSI IDs for a Rackmount TL881 or TL891 DLT MiniLibrary
After the base units have been reconfigured as slaves, each base unit control
panel still provides tape drive status and error information, but all control
functions are carried out from the expansion unit control panel. This
includes setting the SCSI ID for each of the tape drives present.
To set the SCSI IDs for the tape drives in a TL881 or TL891 DLT MiniLibrary
rackmount configuration, follow these steps:
1. Apply power to the MiniLibrary, ensuring that you power up the
expansion unit after or at the same time as the base and data units.
2. Wait until power-on self-tests (POST) have terminated and the
expansion unit and each base and data unit display the default screen.
3. At the expansion unit control panel, press the Enter button to display
the Main Menu.
4. Press the down arrow button until the Configure Menu item is selected,
and then press the Enter button to display the Configure submenu.
5. Press the down arrow button until the Set SCSI item is selected and
press the Enter button.
6. Press the up or down arrow button to select the appropriate tape drive
(DLT0 Bus ID:, DLT1 Bus ID:, DLT2 Bus ID:, and so on) or library
robotics (Library Bus ID:) for which you wish to change the SCSI bus
ID. In a configuration with three base units, and assuming that each
base unit has two tape drives, the top base unit contains DLT0 and
DLT1. The next base unit down contains DLT2 and DLT3. The next
base unit contains DLT4 and DLT5. The default SCSI IDs, after being
reconfigured by the expansion unit, are as follows:
• Library Bus ID: 0
• DLT0 Bus ID: 1
• DLT1 Bus ID: 2
• DLT2 Bus ID: 3
8–72 Configuring a Shared SCSI Bus for Tape Drive Use