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Date: Mon, 22 Nov 2004 18:28:17 -0500
From: Brian Fundakowski Feldman <green@freebsd.org>
To: David Gilbert <dgilbert@dclg.ca>
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	<419BB453.70205@elischer.org> <16795.46413.508033.379777@canoe.dclg.ca>
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cc: freebsd-hackers@freebsd.org
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cc: Julian Elischer <julian@elischer.org>
Subject: Re: Snapshot corruption.
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On Wed, Nov 17, 2004 at 03:32:13PM -0500, David Gilbert wrote:
> >>>>> "Julian" == Julian Elischer <julian@elischer.org> writes:
> 
> Julian> David Gilbert wrote:
> 
> >> I've got a medium busy server (few thousand mail messages a day,
> >> web, webmail, imap, etc) that I can fairly reliably reproduce
> >> filesystem corruption by creating multiple snapshots and deleting
> >> them.
> >> 
> >> I don't think I'm up to debugging this, but I may be able to
> >> provide an exercise platform.
> 
> Julian> can you characterise the corruption?
> 
> Sure.  Typically the system will crash with an ffs panic of some
> random type.  When it comes back, we run non-background fsck's because
> manual fsck is sometimes required.
> 
> Corruption varies.  Some stuff sometimes pops up in lost+found.  Some
> stuff can vanish (not 100% positive on that).  But most worringly, is
> that some files come back corrupted (ie berkley db files that db won't
> read).

Long strings of NUL bytes?  Missing data?  Spam (from the same file,
or from other files)?

-- 
Brian Fundakowski Feldman                           \'[ FreeBSD ]''''''''''\
  <> green@FreeBSD.org                               \  The Power to Serve! \
 Opinions expressed are my own.                       \,,,,,,,,,,,,,,,,,,,,,,\