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Date: Thu, 28 Apr 2011 12:15:42 +0300
From: Daniel Kalchev <daniel@digsys.bg>
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Subject: Re: correct way to setup gmirror on 7.4?
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On 28.04.11 01:30, Freddie Cash wrote:
> gmirror doesn't touch the start of the disk, but saves it's metadata
> in the last sector of the disk, and creates a new GEOM provider that's
> one sector shorter.
>
> GPT stores it's partition table in the first sector of the disk, and
> saves a backup copy of it in the last sector of the disk.
This looks like layering issue to me.

In theory, both gmirror and gpt should work on 'providers'. So if you 
give an gmirrored provider to gpt it should touch the last sector of the 
gmirror, but not the last sector of the disk - and not complain. It 
should not even be able to see the last sector of the real disk.

Is this hard to fix?

Daniel