From owner-freebsd-questions@FreeBSD.ORG Fri Jan 6 19:32:16 2012 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 4DACB1065676 for ; Fri, 6 Jan 2012 19:32:16 +0000 (UTC) (envelope-from wblock@wonkity.com) Received: from wonkity.com (wonkity.com [67.158.26.137]) by mx1.freebsd.org (Postfix) with ESMTP id DFD348FC14 for ; Fri, 6 Jan 2012 19:32:15 +0000 (UTC) Received: from wonkity.com (localhost [127.0.0.1]) by wonkity.com (8.14.5/8.14.5) with ESMTP id q06JWEiq051070; Fri, 6 Jan 2012 12:32:14 -0700 (MST) (envelope-from wblock@wonkity.com) Received: from localhost (wblock@localhost) by wonkity.com (8.14.5/8.14.5/Submit) with ESMTP id q06JWEeV051067; Fri, 6 Jan 2012 12:32:14 -0700 (MST) (envelope-from wblock@wonkity.com) Date: Fri, 6 Jan 2012 12:32:14 -0700 (MST) From: Warren Block To: Bas Smeelen In-Reply-To: <4F072484.9070100@ose.nl> Message-ID: References: <20120105144204.d419cca4.web@3dresearch.com> <6ABAC46B-6193-47B6-B173-94D060E01EC4@mac.com> <4F069A44.7020600@ose.nl> <4F070CA6.5050803@ose.nl> <4F072484.9070100@ose.nl> User-Agent: Alpine 2.00 (BSF 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7 (wonkity.com [127.0.0.1]); Fri, 06 Jan 2012 12:32:14 -0700 (MST) Cc: freebsd-questions@freebsd.org Subject: Re: Apparently conflicting smartctl output X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 06 Jan 2012 19:32:16 -0000 On Fri, 6 Jan 2012, Bas Smeelen wrote: > On 01/06/2012 04:37 PM, Warren Block wrote: >> On Fri, 6 Jan 2012, Bas Smeelen wrote: >> >>> On 01/06/2012 03:39 PM, Warren Block wrote: >>>> On Fri, 6 Jan 2012, Bas Smeelen wrote: >>>> >>>>> I have had this with a drive and multiple read errors would not remap >>>>> the >>>>> sector. >>>>> With write errors the sector would be remapped. This was a new Samsung >>>>> laptop drive though, not a Western Digital. >>>> >>>> That's standard. Sectors are only remapped to spares on a write error. >>>> >>>>> To get the sector remapped I had to fully write the drive and it was ok >>>>> after that. >>>> >>>> Just writing to the sector should be enough. Of course, when one sector >>>> goes bad, others often follow. >>> >>> I just hope it does not develop more bad sectors. >> >> That's the worrying thing. Was it just a loose flake of oxide, or was it a >> strip that peeled off the disk? > > No way to know I guess >> >>>> From what I read on the "Bad block HOWTO for smartmontools" on >>>> sourceforge >>> it's not trivial to just write to that sector and also it would destroy >>> the >>> filesystem? >> >> Finding the right block may not be too hard. /var/log/messages should show >> the block number, but then I don't know what tool is available to write to >> that specific block. Tools like that are not common because generally, >> growing bad sectors means the drive is starting to fail anyway. > > I could use dd if=/dev/random of=file seek=blocks_to_skip bs=100M the next > time Yes, if you're not worried about existing data. But use /dev/zero (faster and you can verify the value) and bs=1M count=100 (ties up only 1M of buffer space).