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Date: Tue, 23 Jan 2007 12:38:06 -0600
From: Eric Anderson <anderson@freebsd.org>
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Subject: Re: clear metadata using dd?
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On 01/23/07 12:30, Oliver Fromme wrote:
> Hi,
> 
> I just noticed this message today, and there's one thing
> I don't understand ...
> 
> Fernan Aguero wrote:
>  > I'm trying to set up two disks to contain both gmirrored and
>  > gstriped slices.
>  > 
>  > This is what I'm trying to achieve:
>  > adxs1, swap
>  > adxs2, gmirror
>  > adxs3, gstripe
> 
> Can someone please explain why such a setup makes sense?
> 
> As far as I can tell, the purpose of gmirror is to provide
> redundancy in the case of drive failure.  I.e. if one
> drive fails, the system keeps running happily instead of
> crashing.
> 
> But if only part of the disk is mirrored, then the system
> will still crash if one drive fails.  So what is the point
> of using gmirror, if not on whole disks?


You might crash, but the data on the mirror on one of the disks is still 
there, so you haven't lost all the data.

Eric