Apple Workgroup Server 8550 - Manual (Page 57)

5 Slide the disk drive bracket out and disconnect the SCSI ribbon cable from the
bottom drive.
To release the bracket, push down the plastic tab just below the bracket.
6 Confirm that the new disk drive is terminated and has its own, unique ID number
between 0 and 6.
Since the new disk drive your are installing will be the last internal device on
the internal/external SCSI bus, you must make sure that the drive is
terminated. To terminate the drive, follow the drive manufacturer’s
specifications.
See the previous section, “Setting the SCSI ID Number,” for details on
selecting and setting ID numbers.
48 Chapter 3 / Expanding Your Server and Connecting Other Equipment