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SCSI Problem

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by bob47301 2 views

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Hi,
I am TRYING to add SCSI harddrives to an existing NT 4.0 server (sp6a). It has an Adaptec 2940U2W card, a CD & an HP DAT drive on the 50 pin connector and an IBM Ultra2 DNES 9.1 on the 68pin LVD connector. I need to add additional drives on the 68 pin connector. I have tried 5 different drives so far. Now I have WD 18.2 Ultra2 drives, which Adaptec & WD have both said SHOULD work. When I add the WD drive & boot, I get a stop error (inaccessable boot device). I have tried new cables, new terminator, setting the WD to force SE. Partitioning the WD by itself & installing NT (also get an error message on trying to load NTFS driver)
Any suggestions? I have done this before with no problem. Everyone says it SHOULD work (I KNOW!!!) Help!

Bob - Lost is SCSI HELL.

7 replies

by stillatit

Re-check all the simple stuff that you are sure you did right by instinct, and you will probably find the glitch.

Are you sure your new drive does not duplicate a SCSI address that is already on the bus (including the adaptor)?

Does the new drive have a built-in terminator? (If that makes one too many terminators, you lose.)

Typically your boot device will be SCSI device 0. Which drive is that? Is your new drive set there?

Where is pin 1 on the connector? Does it match pin 1 on thecable? This sounds stupid, but some companies have connectors installed "upside down" relative to others.

If you pull off the new drives does everything else still work? (Did the cables get loosened or pulled from the host adaptor, or put back onreversed?)

Each drive adds length to the SCSI chain via its internal wiring. Are you now over the max for the chain?

Are the new drives spinning up (you could have a bad power connector or Y adaptor)?

Good luck (sounds like you are due some).

by dcosgrove

Those were pretty much my thoughts. Correct scsi addresses and proper termination point.

by erdo

I just went thru a similar situation by replacing an old SCSI contoller with a new Ultra Wide controller. Moved the old devices (a booting Seagate 2G HD, an HP tape drive and the CD-ROM) to the 50-pin connector. Installed a new WD 18.3 GB WD Enterprise HD to the 68-pin connector.

The new WD hard drive refused to be recognized. Playing with the jumper configurations I finally got it to be recognized, but it echoed itself 14 times. The BIOS was reporting the WD drive multiple times over.

At the end I ignored all recommendations from WD and stripped it to a basic jumper configuration. Pins 21 and 22 were jumped originally from factory (disable Wide negotiation). So I jumped these pins again. The only other pins I jumped were those needed to set the SCSI address (pins 1&2 and 5&6 for SCSI Address 5).

The last step, I removed all cable terminations. The device was then properly recognized.

If you want to add a termination, try a passive terminator rather than an active terminator. Alternatively, terminate the 50-pin cable only. For me, no terminations whatsoever works good.

I can't explain why, but the above simplified configuration worked for me. It has to do with the internal design of the new drives. Hope this works for you, too.

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