SCSI problem...possibly a termination issue?
 

I have an IBM x350 that I cannot get to recognize multiple scsi drives.

For those not familiar with the system, the scsi controller is onboard, and the cable runs to a backplane that controls 3 drive bays.

Here is what I'm experiencing:

They system will recognize one drive inserted into any of the bays. As long as there are no other drives present, it will recognize them fine.

it will recognize any of the drives, so long as there is only one.

When I insert two drives, it won't find either of them.

Here are the specs on the drives:

IBM 9.1G SCSI 80 pin 10K rpm drives

They have the following jumpers on each drive:

SCSI SE/LVD CONNECTOR
------------------------------------
RESERVED
RESERVED
RESERVED
PARITY DISABLED
WRITE PROTECT
MOTOR START ENABLE
DELAY MTR START
FORCE SINGLE ENDED


HDA
------------------------------------
down arrow, going into a "T"
RES
8
4
2
1

I'm new to scsi, but I believe the #s are to set the device address, and the down arrow into the T is to terminate, and I have tried terminating both drives, either drive, and neither drive, and no combination will allow the system to recognize both drives when they are both in the bay.

I may be off-base here, but I don't believe the issue could lie with either drive since both work independently, and I don't believe it could be with the scsi controller since it will control one of the drives. And I also don't believe it could be the bays or the drive trays, since, again...all work fine when only one drive is inserted.

If anyone has any suggestions, or insight, I would greatly appreciate it.

Thanks

i'm not familiear with scsi either, but out of curiousity: what would happen if disabled "force single ended"?

All drives must have a unique device ID. Typically the Controller is assigned 7. So make sure that are not the same.
Only the end devices require termination. i.e. the controller and the last device on the bus. The controller should be ok as is.
LVD means low voltage differential. This drive can use either use LVD or single ended bus. Do not worry if you do not know what all that means. I am not familar with the drive but I guess from the force se that it can automatically use either type. Since the drives are detected I would leave the jumper as is. Make sure they are the same on both drives.

Have you tried using different bays?

What controller is that? Probably some Adaptec but is it the 29160 or the 29320 chipset?

Drive is a hotswap type, right? (80 pin certainly should be).

That server should have a built-in diagnostic indicator inside the case. There will be an LCD readout and you can run the thing through various BIT profiles. I *think* you can also check/set HD configurations from there.