From owner-freebsd-questions@FreeBSD.ORG Wed Jan 25 07:17:00 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 7A2271065674 for ; Wed, 25 Jan 2012 07:17:00 +0000 (UTC) (envelope-from fritz-bounce@frell.theremailer.net) Received: from frell.theremailer.net (unknown [IPv6:2002:d527:dca5:9:ad56:1ea:53f9:c981]) by mx1.freebsd.org (Postfix) with ESMTP id D243A8FC19 for ; Wed, 25 Jan 2012 07:16:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=frell.theremailer.net; s=remailer; h=Date:Message-ID:Subject:Comments:From; bh=rpY12m60vwAECGKOogXRiZrrDihPLLR7l71KuVnDMV4=; b=APO2A/t39huSoW/elM37ujtEDAs5J3vYv4AEwuwaEe+RiAyiFeC2hxfWqxNdQZhLoBdsNqqpYAwuhAia5tlWYqNifwj+Gh+5tHOnVH0urbaLHQK0nYfmKWLfNPzBpzRPKNSeGTU4ZvCFkzmSSeghlCWZ2Zi+T7teRqWtUIUDX5qqG8739rPLWCnL+eBXUjqKxV9T1/2UvdEKeNGxyOb969rOldVL7AAZc5vlTyp54rjxJKINE6KreaLpMvEdRHT+32PpQUUilqbxII4WETo4AcK4eShiSWjWPvz75PVXkNDR5pzuFKYN41iwk19ToP1E9RSoWojj2g4eTcflbwdGSiY=; Received: by frell.theremailer.net with local (Exim) id 1Rpx2u-0000gv-Kq for freebsd-questions@freebsd.org envelope-sender fritz-bounce@frell.theremailer.net; Wed, 25 Jan 2012 08:13:28 +0100 From: Fritz Wuehler Comments: This message did not originate from the Sender address above. It was remailed automatically by anonymizing remailer software. Please report problems or inappropriate use to the remailer administrator at . Identifying the real sender is technically impossible. To: freebsd-questions@freebsd.org In-Reply-To: <20120124150217.GA10327@icarus.home.lan> Message-ID: Precedence: anon Date: Wed, 25 Jan 2012 08:13:28 +0100 Subject: Re: zpool detach pool device X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 25 Jan 2012 07:17:00 -0000 > All DBAN does is write {whatever-source-you-choose} to the drive > basically with dd (it's actually a separate wrapper program but it > behaves identically to dd). Just use dd and avoid the hassle of downloading and burning a cd that does dd. dban is nice if you have to do a garage full of machines or are a Windows victim but if you know your way around UNIX why bother with dban? I recently had some drives fail and I did dd from /dev/urandom > 4) If you ever plan on re-using this drive in a system, please do not > use the PRNG method or similar methods ("write random jibberish all over > the drive"). This is almost guaranteed to confuse a system (ANY system) > the next time you insert the disk; data is written to the MBR and > partition table regions which is gobbledegook, resulting in the > underlying BIOS, OS, or anything else trying to parse that data, and > thus begins behaving weirdly/oddly ("what do you mean I can't partition > this disk?" "Yeah, there's an HP/UX partition on this thing, > right..."). I speak from personal experience on this matter. As such, > I always advocate people zero their drives and not to pick the defaults. Interesting. I have never had this happen but I always partition the drives or label them before trying to do anything after a spring cleaning. If this is your only objection to nonzero values it still is a good compromise to dd the whole drive with /dev/urandom and then just blast the MBR from /dev/zero its only 512 bytes.