[sane-devel] sane-find-scanner finds multiple scanners

Gene Heskett gene_heskett@iolinc.net
Mon, 6 May 2002 22:14:26 -0400

On Monday 06 May 2002 10:45 am, Carsten Neumann wrote:
>On Mon, 06 May 2002, Douglas Gilbert wrote:
>> Johan,
>> In your kernel config (assuming you have built that kernel)
>> turn off CONFIG_SCSI_MULTI_LUN . Some SCSI scanners don't
>> react properly to being probed for logical unit numbers
>> (luns). They should only respond to lun==0 but they respond to
>> all eight. That should leave you with:
>>    /dev/scanner
>>    /dev/sg1
>>    /dev/sgb
>> Doug Gilbert
>Usually /dev/sga .. /dev/sgd are symlinks to /dev/sg0 ..
> /dev/sg3, respectively. Also most harddisks will respond at
> every LUN.
>Once again, I can't see any reason why probing all LUNs will
> prevent the scanner from working!
>If you don't _like_ to find devices on every LUN and you don't
> have a SCSI device (e.g.: jukebox) that will require probing
> every LUN you can of course unset the CONFIG_SCSI_MULTI_LUN
> option.
>Otherwise you can increase the number of /dev/sd*, /dev/sg*,
> /dev/scd*, /dev/sr* and probably other SCSI device nodes if you
> need more. See: mknod(1).
>Kind regards

Unsetting the probe all lun's option may not be something he can 
do.  First, I've only seen one scsi drive, a very old one, that 
actually responded to lun #'s other than 0.  Thats not to say 
that there aren't such beasts today.

BUT, he may have to run with this option on in order to find the 
changer mechanism that goes with his tape library.  Most of these 
robots respond at the same scsi bus address as the drive in the 
robot does, but at LUN=1 instead of 0.

So he original poster here may well be stuck, and have to pick 
which mirror he shoots at.  I'd choose the first one in dmesg and 
let the rest jiggle over and break.

Cheers, Gene
AMD K6-III@500mhz 320M
Athlon1600XP@1400mhz  512M
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