From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Thu, 26 Jul 2001 13:39:38 +0100
Subject: Re: [linux-lvm] Some ideas regarding snapshots (was: Reiserfs, 2.4.7, snapshots w/ 0.9)
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In-Reply-To: <20010726135514.B26425@tiger.bigcats.invalid>; from weissel@netcologne.de on Thu, Jul 26, 2001 at 01:55:14PM +0200
From: Joe Thornber <thornber@btconnect.com>
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On Thu, Jul 26, 2001 at 01:55:14PM +0200, Wolfgang Weisselberg wrote:
> Iain Campbell (iain@sandon.ca) wrote 64 lines:
> > Quote from Teigland and Mauelshagens's Volume Manager whitepaper:
> 
> > journalled file system. These operations (fsck or journal replay) require 
> > writing to  the snapshot ligical volume, which is not allowed."
> 
> On a related subject: would it be possible to have a writable
> snapshot (probably a 'reverse' snapshot)?

Writeable snapshot's are easy to implement, I believe someone has
already made a patch for the current LVM series (search the list).  I
certainly intend putting it into the experimental LVM branch soon.

- Joe