From owner-freebsd-fs@FreeBSD.ORG  Sun Dec 19 05:41:43 2010
Return-Path: <owner-freebsd-fs@FreeBSD.ORG>
Delivered-To: freebsd-fs@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id AF340106564A
	for <freebsd-fs@freebsd.org>; Sun, 19 Dec 2010 05:41:43 +0000 (UTC)
	(envelope-from gpalmer@freebsd.org)
Received: from noop.in-addr.com (mail.in-addr.com [IPv6:2001:470:8:162::1])
	by mx1.freebsd.org (Postfix) with ESMTP id 8436D8FC08
	for <freebsd-fs@freebsd.org>; Sun, 19 Dec 2010 05:41:43 +0000 (UTC)
Received: from gjp by noop.in-addr.com with local (Exim 4.54 (FreeBSD))
	id 1PUC1e-0006N7-46; Sun, 19 Dec 2010 00:41:42 -0500
Date: Sun, 19 Dec 2010 00:41:42 -0500
From: Gary Palmer <gpalmer@freebsd.org>
To: "James R. Van Artsdalen" <james-freebsd-fs2@jrv.org>
Message-ID: <20101219054142.GC70444@in-addr.com>
References: <AANLkTikpYhLFxTp-5ahXQcZTMC5jMTK9Ca+6Xq4VEhhO@mail.gmail.com>
	<4D0D156B.1070402@jrv.org> <4D0D8095.6000106@jrv.org>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <4D0D8095.6000106@jrv.org>
Cc: freebsd-fs@freebsd.org
Subject: Re: ZFS recovery after power failure
X-BeenThere: freebsd-fs@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Filesystems <freebsd-fs.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-fs>,
	<mailto:freebsd-fs-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-fs>
List-Post: <mailto:freebsd-fs@freebsd.org>
List-Help: <mailto:freebsd-fs-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-fs>,
	<mailto:freebsd-fs-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sun, 19 Dec 2010 05:41:43 -0000

On Sat, Dec 18, 2010 at 09:48:37PM -0600, James R. Van Artsdalen wrote:
> On 12/18/2010 2:11 PM, James R. Van Artsdalen wrote:
> > I do know how to recover pools. But I do want to know how it failed.
> 
> Er, I meant to say I do NOT know how to recover pools.
> 
> Sergey's failure doesn't fit any pattern I am familiar with.  Loss of
> power should not have been harmful.
> 
> Perhaps 3ware "cheats" and returns success to SYNC before the disk
> actually completes the command?

3ware controllers can be configured with write-back cache even without
a battery backup, which will almost certainly mean loss of
data if the power is pulled.