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Date: Thu, 19 Feb 2004 03:09:31 -0500 (EST)
From: Andre Guibert de Bruet <andy@siliconlandmark.com>
To: "M. Warner Losh" <imp@bsdimp.com>
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Subject: Re: Review/Test: Pseudo-device unit number management patch
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On Wed, 18 Feb 2004, M. Warner Losh wrote:

> In message: <39796.1077013415@critter.freebsd.dk>
>             "Poul-Henning Kamp" <phk@phk.freebsd.dk> writes:
> : Current our handing is that if it disappears, it's gone, if it comes
> : back it's probably a new one anyway.
>
> Yes.  If the hardware goes away and comes back, it can be very
> difficult to know if you have the same hardware or different
> hardware.  This is less true of network cards, but definitely true of
> CF cards (which can easily be identical from inspection, but have
> different contents).

The likes of ATA disks include serial numbers in words 10-19. These could
be used to positively identify a drive when its availability has come
into question. From what I recall, CF cards use an ATA-like command set.
Wouldn't it be possible to get the serial number and model from them for
positive identification?

Regards,
Andy

> Andre Guibert de Bruet | Enterprise Software Consultant >
> Silicon Landmark, LLC. | http://siliconlandmark.com/    >