Re: Pioneer 6-CD changer (DRM-6324X)

CptDondo wrote:

Tim S wrote:

Host: scsi0 Channel: 00 Id: 00 Lun: 00

immediately before your CDROM is mentioned.

Taking the first 3 numbers, calling them X, Y and Z (OP puts his numbers
in of course), do this:

echo "scsi add-single-device X Y Z 1" > /proc/scsi/scsi
echo "scsi add-single-device X Y Z 2" > /proc/scsi/scsi
echo "scsi add-single-device X Y Z 3" > /proc/scsi/scsi
etc

!@#$!!!!

I'm not sure that's even documented properly - I think I found it mentioned
in the kernel source. It's worked reliably since 2.4 through 2.6 though...

Could you use that to "hotplug" scsi?

I have a really nice SCSI scanner I use only occasionally, so I
typically leave it off. Could this be used to get the system to
recognize it once I turn it on while the system is running?

Yes - typically this technique works on any SCSI device that may come and
go - I used to use it a lot on systems with RAID arrays (proper ones in big
boxes) as adding an array (typically after adding extra disks in spare
bays) would present the new "device" as a LUN, and I didn't want to reboot
a fileserver just to add more storage unless really necessary.

Boot with your scanner on, do the cat /proc/scsi/scsi bit and note the 4
magic numbers - the 3rd one, the SCSI ID should be meaningful as the one
you may have set on the DIP switches or whatever - the LUN (4th entry) will
probably be 0. If you have a single channel SCSI card, the 2nd number will
also probably be 0 and the 1st number, the host ID will be whatever linux
feels like, but it's stable unless you add SATA disks or more SCSI or fiber
channel adapters - or upgrade the kernel, in which case driver probing
order changes may upset it.

You could make a script for convenience then.

HTH

Tim
.

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