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From: Lev Serebryakov <lev@FreeBSD.org>
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Cc: daniel@digsys.bg, freebsd-current@freebsd.org, ivoras@freebsd.org,
	freebsd-geom@freebsd.org
Subject: Re: RFC: Project geom-events
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Hello, Perryh.
You wrote 7 =EE=EA=F2=FF=E1=F0=FF 2011 =E3., 18:06:38:

>>   GPT (and MBR) metadata placement is dictated from outside world,
>> where is no GEOM and geom_label. They INTENDED to be used on DISKS.
>> BIOSes should be able to find it :)

> Certainly GPT and MBR must place an instance of the partition table
> where the BIOS expects it, but there's no immediately obvious reason
> why they must regard that instance as their GEOM metadata.  GPT puts
> a second copy in the provider's last block, and AFAICT it could just
> as well use _that_ instance -- or even a differently-formatted block
  GPT must have backup copy in last sector by standard, it is not
caprise of GEOM class author.. BIOSes could refuse to boot from it, if
they don't find second copy. And it could occupies not only one sector,
but up to 34 of them.

> that included the same data -- as the primary.  MBR could do likewise.
  MBR doesn;t have any additional metadata. How adding one will help
 it?

--=20
// Black Lion AKA Lev Serebryakov <lev@FreeBSD.org>