unlikely secondary GPT LBA

[Joan Picanyol i Puig]

Andrey V. Elsukov <bu7cher <at> yandex.ru> writes:

> 
> On 27.07.2010 21:19, Joan Picanyol i Puig wrote:
> > # add boot partition, aligning it's end to 1MB boundary
> > gpart add -b 64 -s 1984 -t freebsd-boot -l boot /dev/mirror/system
> 
> Do your system successfully boots from this partition?

Well, I'm currently unable to answer this question. Both drives are behind the 
same twa controller (3Ware 9650) and I've been unable to change the boot disc 
from the BIOS (over serial). Not surprisingly, the currently installed by 
default boot0 does not know how to pass control to a loader in a GPT partition.

> > I must be misunderstanding something, because I see this as gpart
> > deciding that my secondary GPT header is at LBA FD3F1A1D00000000 which
> > way past the end of my disk.
> 
> It's in little-endian bytes order. I think it is 0x1D1A3FFD on your system.

Duh, of course. This matches with reality:

charlie# diskinfo /dev/da1 | cut -f 4
488259584

So, what explains the messages? gpart probes the disk before gmirror (or at 
least it prints later on dmesg), but since the offset is in the header, it 
should not even know about the gmirror + glabel part.

I still don't understand something...

tks
--
pica

p.s.: sorry for the bounce, should be fixed now