From owner-freebsd-fs@FreeBSD.ORG Mon Jun 7 08:34:30 2010 Return-Path: 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 6E44E1065686 for ; Mon, 7 Jun 2010 08:34:30 +0000 (UTC) (envelope-from jdc@koitsu.dyndns.org) Received: from qmta07.emeryville.ca.mail.comcast.net (qmta07.emeryville.ca.mail.comcast.net [76.96.30.64]) by mx1.freebsd.org (Postfix) with ESMTP id 3D7618FC0A for ; Mon, 7 Jun 2010 08:34:29 +0000 (UTC) Received: from omta02.emeryville.ca.mail.comcast.net ([76.96.30.19]) by qmta07.emeryville.ca.mail.comcast.net with comcast id SwZZ1e0040QkzPwA7waV7u; Mon, 07 Jun 2010 08:34:29 +0000 Received: from koitsu.dyndns.org ([98.248.46.159]) by omta02.emeryville.ca.mail.comcast.net with comcast id SwaU1e0043S48mS8NwaUfD; Mon, 07 Jun 2010 08:34:29 +0000 Received: by icarus.home.lan (Postfix, from userid 1000) id 6EBA29B418; Mon, 7 Jun 2010 01:34:28 -0700 (PDT) Date: Mon, 7 Jun 2010 01:34:28 -0700 From: Jeremy Chadwick To: Andriy Gapon Message-ID: <20100607083428.GA48419@icarus.home.lan> References: <4C0CAABA.2010506@icyb.net.ua> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4C0CAABA.2010506@icyb.net.ua> User-Agent: Mutt/1.5.20 (2009-06-14) Cc: freebsd-fs@freebsd.org Subject: Re: zfs i/o error, no driver error X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 07 Jun 2010 08:34:31 -0000 On Mon, Jun 07, 2010 at 11:15:54AM +0300, Andriy Gapon wrote: > During recent zpool scrub one read error was detected and "128K repaired". > > In system log I see the following message: > ZFS: vdev I/O failure, zpool=tank > path=/dev/gptid/536c6f78-e4f3-11de-b9f8-001cc08221ff offset=284456910848 > size=131072 error=5 > > On the other hand, there are no other errors, nothing from geom, ahci, etc. > Why would that happen? What kind of error could this be? I believe this indicates silent data corruption[1], which ZFS can auto-correct if the pool is a mirror or raidz (otherwise it can detect the problem but not fix it). This can happen for a lot of reasons, but tracking down the source is often difficult. Usually it indicates the disk itself has some kind of problem (cache going bad, some sector remaps which didn't happen or failed, etc.). What I'd need to determine the cause: - Full "zpool status tank" output before the scrub - Full "zpool status tank" output after the scrub - Full "smartctl -a /dev/XXX" for all disk members of zpool "tank" Furthermore, what made you decide to scrub the pool on a whim? [1]: http://blogs.sun.com/elowe/entry/zfs_saves_the_day_ta http://blogs.sun.com/bonwick/entry/zfs_end_to_end_data http://blogs.sun.com/bonwick/entry/raid_z -- | Jeremy Chadwick jdc@parodius.com | | Parodius Networking http://www.parodius.com/ | | UNIX Systems Administrator Mountain View, CA, USA | | Making life hard for others since 1977. PGP: 4BD6C0CB |