RFC: Project geom-events

[Lev Serebryakov]

Hello, Daniel.
You wrote 8 октября 2011 г., 0:13:54:

>>>>    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
>>> that included the same data -- as the primary.  MBR could do likewise.
>>    I have deja-vu, that I answered this. Please, read standard. GPT
>>   _must_ be placed twice -- at first and last sectors (really, more
>>   than one sectors). By standard. Secondary copy must be at end of
>>   disk. Period.
> Then, "by standard" GPT cannot coexist with GLABEL. Such setup should be
> disallowed, or at least big nasty message that you have just shoot 
> yourself in the leg should be output. (period)
  Ok, maybe adding check to geom_part, that it is used on rank-1
 provider (whole disk) is not so bad idea. But it then raise question
 how to install FreeBSD on software mirror, what is useful. But could
 bite you sometimes... Hm...

-- 
// Black Lion AKA Lev Serebryakov <lev at FreeBSD.org>