SCSI Adapter Compatiblity

[kseverson]

As I've mentioned before on this list, I have several P390 systems that are of the Integrated Server variety. They came installed with differential SCSI adapters. As I have no peripherals of that flavor I replaced the adapters with Adaptec 2940W/2940UW ones. They were sent to me by the system supplier but came with no software. I can't remember the model of the differential adapters as I'm not at work but I think they were 2944's. If the system has the Adaptec 7800 "family" of drivers installed, would it be a fair assumtion that they'd run these single ended adapters as well or would they be for differential only? The systems run OS/2 and VM/ESA 2.3 on top of that. All VM tape commands and DDR work on the drives but the Sterling (CA) VM:Manager's VM:Tape won't mount tapes and just stalls out with an interrupt. I'm wondering if it's a hardware or software (or both) problem. Any ideas?
Thanks!
Karl Severson
Raytheon Systems Company

 

[lej]

A few things to look at.

First you will need the OS/2 7800 fam drivers for the 2940 adapters.

Second, I suggest you change 3 settings for the tape drive. in the SCSI Select go into Adapter configuration/device configuration. then change the following for the SCSI ID of the tape drive. 1. set data transfer rate to 5MB, 2. Set widenegotations to No and 3. set Send start unit command to no.

Be sure the SCSI cables are terminated correctly, each end of the bus only and the full 16bit data with. This means you cannot use a 50 pin SCSI device to terminate a 68 Pin cable. If you do, your upper 8 bits wil not be terminated.

That should make the system much happier..

 

[kseverson]

I'm going to close this one out. I have instituted a work around which eliminates the VM:Tape MOUNT command by taking VM:Tape out of the backup scenario. I have set it up so that VM:Backup takes care of the backups and the tape pools and I just have an EXEC which attaches a tape drive to VMB after the backups are submited. The IBM reseller was of the opinion that the newer SCSI drivers on these servers did not support non-IBM tape drives. I tried the older ISITAPE drivers but they did not solve the problem. At any rate, I consider the problem solved now.
Karl