From owner-freebsd-questions@FreeBSD.ORG Tue Jun 10 14:59:31 2008 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 32A31106564A for ; Tue, 10 Jun 2008 14:59:31 +0000 (UTC) (envelope-from erikt@midgard.homeip.net) Received: from ch-smtp01.sth.basefarm.net (ch-smtp01.sth.basefarm.net [80.76.149.212]) by mx1.freebsd.org (Postfix) with ESMTP id B93318FC1E for ; Tue, 10 Jun 2008 14:59:30 +0000 (UTC) (envelope-from erikt@midgard.homeip.net) Received: from c83-253-25-183.bredband.comhem.se ([83.253.25.183]:59924 helo=falcon.midgard.homeip.net) by ch-smtp01.sth.basefarm.net with esmtp (Exim 4.68) (envelope-from ) id 1K65Jp-0003me-5j for freebsd-questions@freebsd.org; Tue, 10 Jun 2008 16:59:29 +0200 Received: (qmail 76312 invoked from network); 10 Jun 2008 16:59:26 +0200 Received: from owl.midgard.homeip.net (10.1.5.7) by falcon.midgard.homeip.net with ESMTP; 10 Jun 2008 16:59:26 +0200 Received: (qmail 67035 invoked by uid 1001); 10 Jun 2008 16:59:26 +0200 Date: Tue, 10 Jun 2008 16:59:26 +0200 From: Erik Trulsson To: DA Forsyth Message-ID: <20080610145926.GA66984@owl.midgard.homeip.net> References: <484EACEB.7169.43FE1258@iwrtech.iwr.ru.ac.za> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <484EACEB.7169.43FE1258@iwrtech.iwr.ru.ac.za> User-Agent: Mutt/1.5.18 (2008-05-17) X-Originating-IP: 83.253.25.183 X-Scan-Result: No virus found in message 1K65Jp-0003me-5j. X-Scan-Signature: ch-smtp01.sth.basefarm.net 1K65Jp-0003me-5j c2e079f9f194f79cf7467cbb76813882 Cc: freebsd-questions@freebsd.org Subject: Re: xRAID disks.... 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: Tue, 10 Jun 2008 14:59:31 -0000 On Tue, Jun 10, 2008 at 04:33:47PM +0200, DA Forsyth wrote: > Hiya > > I've had this for a while now and have done many searches for info > but have not yet come up with the right question, hence have not got > the answer. > > My main server has an Adaptec IDE raid card. A couple of years ago I > took disks that had been a mirror pair on that card out of the server > and put them into my test server, not as a raid pair since the test > server has no raid hardware. > > During boot I see this > ad0: 19092MB at ata0-master UDMA66 > ad1: 76319MB at ata0-slave UDMA66 > ad2: 76319MB at ata1-master UDMA66 > ad3: 19092MB at ata1-slave UDMA66 > ar0: 76319MB status: BROKEN > ar0: disk0 DOWN no device found for this subdisk > ar0: disk1 DOWN no device found for this subdisk > > The pair of ex-RAID disks are ad1 and ad2 and obviously are no longer > a raid pair, yet 'something' is telling the ar() driver to try and > pair them and failing because there is no raid hardware in that box. > > Now I am reconfiguring that machine a bit and would like to fix this, > both on these existing drives and on the 320MB drive I have just > removed from a RAID1 pair and will be putting into the box instead of > ad3 (the other 320GB from the pair is in a USB enclosure for other > purposes and has not shown any signs of knowing it was in a raid > pair) > > I suspect the raidinfo is stored on the disk somewhere and a suitable > 'dd' command can erase it. but where and how? That kind of information is usually stored last on the disk (where it is least likely to be overwritten by filesystems, partitioning info, or boot loaders), so if you overwrite the last couple of KBs on those disks you will probably be fine. (If you want to be certain you can always use 'dd' to nuke all the information on the disk. That will take longer time, but you get the extra advantage of testing all the blocks on the disk so that they work correctly.) For the first you could do something like: dd if=/dev/zero of=/dev/ad1 bs=1m skip=76318 which should overwrite the last MB of ad1 with zeros. To erase all of the disk: dd if=/dev/zero of=/dev/ad1 bs=1m -- Erik Trulsson ertr1013@student.uu.se