Re: PATCH: cdrecord: avoiding scsi device numbering for ide devices

Alan Cox
2004-08-07T23:11:24Z

On Sad, 2004-08-07 at 01:01, Joerg Schilling wrote:
> >There is one: hotplug. The physical topology of buses where all the SCSI-like
> >devices (being it ATAPI devices, iSCSI, USB disks or other such beasts)
> >are connected is too complex, so every attempt to map them to the
> >(bus, target, lun) triplets in any sane way is destined to fail.
>
> I see always the same answers from Linux people who don't know anyrthing than
> their belly button :-(
>
> Chek Solaris to see that your statements are wrong.

Solaris also can't handle the problematic cases. One of the big problems
being that bus, target, lun (or controller, bus, target, lun) are not
actually constants in all cases.

On some Dell storage arrays for example the disks are
bus 0, target 0..4 bus 1, target 0..4 - until that is the cleaner
trips over one of the SCSI cables at which point it becomes bus 0,
lun 0...9, live, while running.

An even more fun one is SCAM, although its a mostly dead nonstandard
thankfully. With SCAM you can get your devices changing target across
a suspend/resume.

BTW while I remember cdrecord has a bug with hardcoded iso8859-1
copyright symbols in it which mean your copyright banner is invalid
unicode on a UTF-8 locale.