From owner-freebsd-questions@FreeBSD.ORG Thu Jun 12 08:22:28 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 B3546106567F for ; Thu, 12 Jun 2008 08:22:28 +0000 (UTC) (envelope-from iwrTech@iwr.ru.ac.za) Received: from c.mail.ru.ac.za (c.mail.ru.ac.za [IPv6:2001:4200:1010::25:3]) by mx1.freebsd.org (Postfix) with ESMTP id 403B88FC12 for ; Thu, 12 Jun 2008 08:22:28 +0000 (UTC) (envelope-from iwrTech@iwr.ru.ac.za) Received: from iwr.ru.ac.za ([146.231.64.249]:56948) by c.mail.ru.ac.za with esmtp (Exim 4.68 (FreeBSD)) (envelope-from ) id 1K6i4h-000EFM-01 for freebsd-questions@freebsd.org; Thu, 12 Jun 2008 10:22:27 +0200 Received: from iwr61.iwr.ru.ac.za ([146.231.64.161]) by iwr.ru.ac.za with esmtp (Exim 4.69 (FreeBSD)) (envelope-from ) id 1K6i4h-0001Mr-0L for freebsd-questions@freebsd.org; Thu, 12 Jun 2008 10:22:27 +0200 From: "DA Forsyth" Organization: IWR To: freebsd-questions@freebsd.org Date: Thu, 12 Jun 2008 10:22:25 +0200 MIME-Version: 1.0 Message-ID: <4850F8E1.11972.4CF6D470@iwrtech.iwr.ru.ac.za> Priority: normal In-reply-to: <4850EB8B.12487.4CC2C0F4@iwrtech.iwr.ru.ac.za> References: <484EACEB.7169.43FE1258@iwrtech.iwr.ru.ac.za>, <20080610145926.GA66984@owl.midgard.homeip.net>, <4850EB8B.12487.4CC2C0F4@iwrtech.iwr.ru.ac.za> X-mailer: Pegasus Mail for Windows (4.41) Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: 7BIT Content-description: Mail message body X-Virus-Scanned: c.mail.ru.ac.za (146.231.129.35) Subject: Re: xRAID disks.... X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: iwrTech@iwr.ru.ac.za List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 12 Jun 2008 08:22:28 -0000 On 12 Jun 2008 , DA Forsyth entreated about "Re: xRAID disks....": > hmmm, thinking now the gmirror create/remove route will probably > work. let me try it on a blankish disk and see.... this appears to be the answer to the question: how to stop ar recognizing a disk that used to be on a raid controller doing a 'gmirror label gm0 /dev/ad1' filled the last sector with data, and 'gmirror clear /dev/ad1' reset it all to zero now to try it on the big disk with data on it... YES: it works, and the data slice is still there, and the commands happen a lot faster than a dd with a skip parameter sidenote: to see the last sector use sysinstall's fdisk to see the data for the disk. you'll see something like Disk name: ad3 FDISK Geometry: 38913 cyls/255 heads/63 sectors = 625137345 sectors Offset Size(ST) End Name PType Desc Subtype 0 63 62 - 12 unused 0 63 625137282 625137344 ad3s1 8 freebsd 165 625137345 5103 625142447 - 12 unused 0 ^^^^^^^^^ you want that number in a dd commmand like this dd if=/dev/ad3 skip=625142447 | hd -v Thanks to all for the pointers -- DA Fo rsyth Network Supervisor Principal Technical Officer -- Institute for Water Research http://www.ru.ac.za/institutes/iwr/