Linux, SCSI Adaptec problem

The system is a fairly basic AMD socket A with 512Mb RAM, running Fedora core 6. (yes a bit underpowered, but that is being addressed, and I think has little bearing on the problem) There is an advansys SCSI 1 card that drives an old SCSI ZIP drive, which works well under FC6.

I have recently bought a used Adaptec 39160 lvd SCSI card and an appropriate tape drive for backups. The adaptec card is installed at an earlier slot than the advansys card.

The SCSI card boots and recognises the tape drive quite happily, but the system hangs during the intial start up phase when udev is probing for new hardware. It eventually ends with a "kernel panic - not syncing: loop1" message.

Disk space is low on this system (also being addressed) so my first thought was that there was too little space to load te driver, so I booted the system from a Knoppix live CD version 3.8.2. This booted, but hung at the point "loading aic7xxx.so which is the driver for the adaptec card.

I then tried booting from a Knoppix 3.7 live CD. This booted OK, loaded the aic7xxx driver, went on to load the advansys driver, booted normally and a I can control the tape drive using the mt command - so I know that the card, drive and system are capable of working together.

Final step was to run the FC6 install CD - not to re-install, but just to run the system probe without running into hard drive problems (if they exist).

Again the system hangs at the loading aic7xxx driver stage. I also removed the advansys card, in case there was an incompatability issue, but the same thing happens. (FC 6 loaded the advansys driver first.)

So clearly a driver issue, but I'm not sure if it is kernel 2.6 related or not - but it seems starnge that an early Knoppix version should work while a later version doesn't.

Any clues or possible remedies greatfully received, before I start firing off support requests to Adaptec (not the best) or Tandberg (tape drive mfr).

Thanks - Peter

(Edit - not a lot of info on Google either - although there is a hint, so downloading the latest Kernel might help - still grateful for any other insight though)

(Edit 2 - If the tape drive is disconnected from the SCSI card, the system boots, although it does seem to take a bit longer at teh udec stage)

definitely no conflicts on scsi id numbers, and terminators used appropriately?

Only one device on it - which is properly terminated - and as I say, works with Knoppix 3.7. I did wonder if I need to remake initrd... with support built into it, but I don't think that is the answer as it won't boot off the install disc.

Also discovered that although the system boots with the tape drive diwsconnected and the SCSI card installed, it won't boot off the install or rescue discs in that configuration.

(Just had a look at the Adaptec site - there is source code for the aicxxx drivers dated Aprik 2007, which may be newer than the current (supplied with the distro) version - so I'll try that - still puzzzled why it won't boot off the install discs though...)

Still investigating - but gets stranger... Apart from the one off, Knoppix 3.7 no longer loads the driver - and the SCSI card doesn't always detect the tape drive on boot up - which would indicate a cabling problem - hoever resetting the card fixes this.

But Windows 2K boots with it, and the drive's test utilities recognise and control the drive, so I am reasonably happy that the drive/cable/SCSI card combination is OK - which comes back to the Linux driver...

some cards have issues, especially on older hardware.

Can you provide details on the motherboard, card version, bios on the card and tape drive attatched to it.

You may have to pass boot options to the kernel to get the driver to load properly, or you may need to disable something thats too new for your board to get detection to run properly. Firmware is also a killer on scsi cards. For Driver version X you'll need firmware version Y for stability.

Cracked it! I'd like to say by careful diagnostic technique and use of live CDs, but it was pretty much a fluke!

I managed to get the early Knoppix disk to boot by using "expert" (ie interactive) mode which made me wonder if my old (its an Asus A7V133 with an Award bios - I built it in 2001 so it is pretty long in the tooth - but then about the same vintage as the adapte4c card) motherboard just wasn't up to it (although it worked under W2K)

I tried various settings onthe SCSI card with no luck, but diid get it to boot under Knoppix 3.8.2 with Kernel 2.6 - again using expert mode and entering the driver module manually. Verbose mode showed that it was failing to map in DMA and was operating in PIO mode, so I wondered if there was a conflict. The card was ahreing IRQs qith the serial ports so I disabled those in the bios. No difference, but when I came to reset the serial port settings, Icouldn't remember the setting so I reset the bios to default.

While I was resetting the few changes, I noted a setting "Plug and play OS" which defaults to no, but of course, when I built this, using Win2K I set that to yes. Leaving it at 'no' forces the bios to set up the hardware initallially - at FC6 booted without any problems.

So simple really! But thanks to Ikonia and Directhex for their input.

(And probably time to update the mobo on this machine)