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November 17, 2005
SCSI IDs for Disk Cards
When you install a disk card (see TechTip: Building an E4500/5500/6500 for more information about disk cards), the SCSI IDs seem to come out strange. There is actually a naming scheme which lets you predict the numbers - useful if you are connecting to the internal SCSI bus.
Note that these default drive address settings are assigned by the centerplane slot position when a jumper is *NOT* installed on J0702 and J0703 Pins 1-2.
- If the Board is in Slot 0, the disks will be 4 and 5 (clash with internal tape units)*
- Slot 1, disks will be 6 and 7 (clash with CD-ROM and motherboard)*
- Slot 2, disks 0, 1
- Slot 3, disks 10, 11 (a, b)
- Slot 4, disks 2, 3
- Slot 5, disks 12, 13 (c, d)
- Slot 6, disks 8, 9
- Slot 7, disks 14, 15
If you have a 6500, there are extra slots:
- Slot 8, disks 10, 11 (a, b) - clash with slot 3, 15
- Slot 9, disks 0, 1 - clash with slots 2, 14
- Slot 10, disks 12, 13 - clash with slot 5
- Slot 11, disks 2, 3 - clash with slot 4
- Slot 12, disks 14, 15 - clash with slot 7
- Slot 13, disks 8, 9 - clash with slot 6
- Slot 14, disks 0, 1 - clash with slots 2, 9
- Slot 15, disks 10, 11 - clash with slots 3, 8
On the other hand, if you jumper J0702 (first disk) or J0703 (second disk), then you can set the SCSI ID manually for the disk. Just avoid 4, 5, and 6 if you want to use the internal SCSI bus.
[* So it is just as well you cannot install a disk board in this slot :-)]
Posted by Ozguru at November 17, 2005 06:00 AM
