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Date: Fri, 15 Sep 2006 10:49:16 +0200 (CEST)
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From: Oliver Fromme <olli@lurza.secnetix.de>
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Subject: Re: gmirror size question
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R. B. Riddick <arne_woerner@yahoo.com> wrote:
 > # diskinfo /dev/md?
 > /dev/md0        512     33554432        65536
 > /dev/md1        512     16777216        32768
 > # gnop create -v -s 10485760 md0
 > # gmirror label fook md0.nop md1
 > # gmirror stop fook
 > # gnop destroy md0.nop
 > # gmirror forget fook
 > # gmirror insert fook md0
 > # gmirror list
 > [...]
 > Providers:
 > 1. Name: mirror/fook
 >    Mediasize: 10485248 (10M)
 > [...]
 > Consumers:
 > 1. Name: md0
 >    Mediasize: 33554432 (32M)
 > [...]
 > 2. Name: md1
 >    Mediasize: 16777216 (16M)

Ah, that's cool.  Thanks for the suggestion, I didn't think
of using gnop for that purpose.  I was rather looking for
a "size" option to gmirror(8), but that doesn't exist.

I've just successfully reproduced your "plan" with several
md devices of various sizes, for testing purposes.  Now
going to do it with the "real" disks.  :-)

Thanks!

Best regards
   Oliver

PS:  I think that hint should be mentioned in the Handbook
section about gmirror.  It could prevent major foot-shoting.
Comments?

-- 
Oliver Fromme,  secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing
Dienstleistungen mit Schwerpunkt FreeBSD: http://www.secnetix.de/bsd
Any opinions expressed in this message may be personal to the author
and may not necessarily reflect the opinions of secnetix in any way.

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