From owner-freebsd-scsi@FreeBSD.ORG  Tue May 13 19:50:00 2003
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From: "Marc G. Fournier" <scrappy@hub.org>
To: Greg 'groggy' Lehey <grog@FreeBSD.org>
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cc: freebsd-scsi@freebsd.org
Subject: Re: RAID5 capacities / usable drive space ...
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On Wed, 14 May 2003, Greg 'groggy' Lehey wrote:

> Hmm.  You know some interesting someones.

Yup ...

> Yes, it doesn't make sense to have a RAID-5 volume with less than three
> drives, but in degraded mode it'll run with two.  Or it should, bar
> implementation constraints.  And theoretically you could hot swap them.

'K, I'm going to test the 'theory' out tomorrow just to make double sure
about the 3->2 drive configuration ... since you already know the vinum
internals, I'm more worried about how hardware RAID will handle things ...

Actually, Scott, are you out there anywhere?  Do you know how the Adaptec
RAID controllers would handle things?

Thanks ...