Gateway ADAC ULTRA2 S466 - Manual (Page 82)

ADAC Ultra2 S466 Hardware Guide 68
Device Identification on ADAC Ultra2 S466
All logical drives on each SCSI bus are identified to the
host as ID 0. Differentiate the drives with Logical Unit
Identifiers (LUNs). ID 0 cannot be used for non-disk
devices because they are limited to IDs 1 through 6. The
ADAC Ultra2 S466 is limited to eight logical drives
because LUNs are used to present logical drives. The
SCSI-2 ANSI specification has a limit of eight LUNs per
ID. The SCSI-3 specification increased the number of
LUNs to 16. An example of ID mapping follows.
Example of ADAC Ultra2 S466 ID Mapping
ID Channel 1
0 A1-1
1 A2-1
2 CD
3 A2-5
4 CD
5 A4-1
6 Optical
7 Reserved
8 A5-2
9 A5-6
10 A6-1
11 A6-4
12 A6-7
13 A7-2
14 A7-5
15 A7-8
As Presented to the Operating System
ID LUN Device ID LUN Device
0 0 Disk (A1-X) 1 0 Scanner
0 1 Disk (A2-X) 2 0 CD
0 2 Disk (A3-X) 3 0 Tape
0 3 Disk (A4-X) 4 0 CD
0 4 Disk (A5-X) 5 0 Tape
0 5 Disk (A6-X) 6 0 Optical
0 6 Disk (A7-X)
0 7 Disk (A8-X)