Understanding Scsi Id Numbers; Setting The Scsi Id Numbers On Your Drives - DEC DECstation 5000 Model 100 Series Hardware Operator's Manual

Understanding SCSI ID Numbers

The workstation distinguishes each internal and external
drive connected to a small computer system interface (SCSI)
connector by the SCSI ID number (0 to 6) assigned to that
drive.
Each drive comes from the factory with a SCSI ID number
already set. These factory settings, called default settings, are
listed in Table 5-1.
Table 5-1. Default SCSI ID Numbers for Internal Drives
Drive Type
RZ23L Hard disk
RZ24 Hard disk
RZ25 Hard disk
RRD42 Compact disc drive
RX23 Diskette drive
RX33 Diskette drive
TZK10 Tape drive
* If the system contains two RZ23L, RZ24, or RZ25 drives, the ID numbers
are preset to 2 and 3 at the factory.

Setting the SCSI ID numbers on your drives

Each drive within a group (or chain) of drives must have its
own unique SCSI ID number (0 to 6), in order to function
properly.
To avoid the problem of duplicate SCSI ID numbers within the
same group, don't use more than one drive that has the same
default setting.
To check for duplicate SCSI ID numbers, you must examine the
settings on your drives, as shown in Appendix D of this guide.
Default Setting
2 (and 3)*
2 (and 3)*
2 (and 3)*
4
5
5
5
Internal Hardware Options 5–27