compression with HP surestore

[Zulan]

Hi!

I have a HP Surestore DAT24i (C1537a) tape device it has the latest bios version L005. It’s connected to an Adaptec 2940u2w SCSI card with the latest bios (July 2001). I have all the dip switches set to standard witch is all the switches set to on except the 3rd one witch is off. The OS is w2k with ms drivers for the devices.

Now we come to my problem. When testing it with HP library and tape tools I get no compression, none what so ever, both on reading and writing I get the compression 1:1.0. This is consistent; I’ve tried about 1 million times. I get no compression from the built in backup software in w2k. I can only get software compression from Veritas backup exec. All this makes me believe that I have a faulty tape drive, well, here’s the killer: If I change the 2nd dipswitch to off, I get hardware compression using HP library & tools but not using any of the 2 mentioned softwares?

I have read that some special settings for the SCSI card is in order so I have changed it to:

Send Start Unit Command: No/Disabled
Enabled Disconnect: Yes/Enabled
Initiate Wide Support: No/Disabled

I’ve read that I should disable sync negotiation, I can’t find that anywhere. I’ve also read that the transfer rate should be 10MB or lower. So what should I set it to, ASYNC or 10MB?

[Zulan]

Any ideas? Please?