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Subjectscsi disk detection and /dev names, RE: My $.02 on the raging de vfs debate
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>     Ok.  I like being able to address SCSI devices by their 
> target ID's too.
> However wouldn't it be simplier to just modify the SCSI
> drive,tape,CDROM,etc
> drivers to have their devices hardcoded to /dev/scsi/c0t0d0 and so on?

this for me is the 'killer' feature of devfs. eg a disk in a server died on
me the other day. so i used the 'echo "scsi add/remove ..." > /proc...'
feature to hot swap it.
without devfs above would have resulted in the disk getting a different name
after rebooting, not nice. with devfs.. no problem. The reason being that
linux keeps track of disks in order of detection, so with a static
preallocated /dev all you can say for sure is that 8:0 will be the first
detected disk, 8:1 the second.. etc. However the scsi disk layer does know
at detection time which host/bus/id/lun the newly detected disk is on, so
with devfs can register a descriptive name for it.

So devfs is a quick workaround of this limitation rather than being a real
cure (for this particular prob). If anyone with the coding skills is
listening, it'd be great if static /dev could support location based disk
names too.

-paul jakma.

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