From owner-freebsd-questions@FreeBSD.ORG Mon Mar 10 16:54:45 2014 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 81FE8BF4 for ; Mon, 10 Mar 2014 16:54:45 +0000 (UTC) Received: from mail-we0-x236.google.com (mail-we0-x236.google.com [IPv6:2a00:1450:400c:c03::236]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 1731CCA for ; Mon, 10 Mar 2014 16:54:44 +0000 (UTC) Received: by mail-we0-f182.google.com with SMTP id p61so9046865wes.27 for ; Mon, 10 Mar 2014 09:54:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=20120113; h=from:to:date:mime-version:subject:message-id:priority:in-reply-to :references:content-type:content-transfer-encoding :content-description; bh=dwCjOTin2Ymle4TI2pdTOaQOU44rPKhYkFTmA/rHTn0=; b=cVN27lR78nDZDW4iGoQKnt/aP1UYYcQc58aODFvDayBfFyKyA5T9iNmdMWghJsLTVD uVUTkWEQPaHYy+Gj8qrFTUTDGLQsbNsPJBvEPaOulxb1sv12563foT88ZPXg0qysrIIH WGeDQ0/DmuM9JQSlJNa7OV6v7VX+jEGaIC0yitNG/GLWiAK6Et8q0ZKo0Wxsq38onoEv xM+cIJdDA8JzEUBNz22VA44nuyd7U61GOzDAlBf3tWD3YYf3UOzMOxmU4qhiHsjrkCb0 vqwyrLeV7kzR+RwR7T8Q/xuBZJ2pqHtoLj4x2Lz6A0xaerZMf8cwTQoQ0DdNifCclOf0 23Cg== X-Received: by 10.194.71.47 with SMTP id r15mr31916966wju.19.1394470483574; Mon, 10 Mar 2014 09:54:43 -0700 (PDT) Received: from [192.168.16.70] ([217.41.35.220]) by mx.google.com with ESMTPSA id q15sm52794425wjw.18.2014.03.10.09.54.41 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Mon, 10 Mar 2014 09:54:42 -0700 (PDT) From: Dave B To: freebsd-questions@freebsd.org Date: Mon, 10 Mar 2014 16:54:33 -0000 MIME-Version: 1.0 Subject: Re: How to destroy a zpool that can no longer be imported? Message-ID: <531DEE49.19752.E8A5B45@g8kbvdave.gmail.com> Priority: normal In-reply-to: <531DE07B.8050704@qeng-ho.org> References: , <531DCE03.30432.E0C4CA2@g8kbvdave.gmail.com>, <531DE07B.8050704@qeng-ho.org> X-mailer: Pegasus Mail for Windows (4.62) Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: 7BIT Content-description: Mail message body X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 10 Mar 2014 16:54:45 -0000 Arthur Chance wrote... > > If you don't mind loosing everthing on the physical disk(s)... > > > > "DBAN" > > > > Darik's Boot and Nuke. http://sourceforge.net/projects/dban/ > > > > Unlike Gpart (and GParted) this will truly errase the disk. > > > > What you end up with a truly clean, and able to be used for whatever you want > > afterwards, with no odd problems. > > > > I found GParted in particular, though it destroys the partition tables OK, it does > > not remove the data on disk that was in the partition. As a result, I had > > terrible troubles a while ago, getting FBSD 9.2 to reload, after I seriously > > screwed something up. GParted didn't do the job, I kept getting strange lib > > errors during the reinstall (from CD.) > > > > DBAN did the job, but it does take time, as it writes random noise to the entire > > physical disk, sector by sector. The re-install after that, just worked, no errors. > > > > The price is right, but take care, once let loose, that's it, there is no turning > > back. > > If all you want to do is clear a disk in order to reinstall it, doing > > dd if=/dev/zero of=$DISK bs=1g > > (possibly from a live CD/DVD) is quicker and doesn't require you to > download and burn an extra ISO. > > Hi Authur. The issue wasn't speed of erasure (anything "fast" usualy does not erase data, just the allocation tables.) What I needed, was a totally virgin disk to re-install on, after I found comments on some lists that the FBSD 9.2 installer can get it's knickers in a twist, if there is already some "familiar structure" on the target disk, after it's done the partition allocation stuff. I found (using other tools) that Gpart/GParted etc, do not erase the partition contents, just the headers and allocation tables. Now, if the new partition layout was significantly different, there probably would not have been an issue, but as I was just letting it do the default thing each time, it was obviously recreating the exact same partition start/end etc settings each time. Once I forced a total scrub, leaving the disk full of psuedo random noise, it re-installed cleanly, from the same exact CD that was failing before. I had burnt a total 3 different copies of the 9.2 install, downloaded via two different systems. I'm sticking with 9.2 for now, while others way more knowlegable than I, knock the sharp edges off 10.0! As to burning ISO's, that's trivial and fast to do for something like DBAN, or Memtest86 (another suspect to test.) In my case, I already had the tools ready to go, I also ran Spinrite, as I was wondering if the drive was bad. (I have my own legit' copy.) I know my way arround those tools, and I know the hardware, + I'm not a BSD guru, so finding such command line stuff as you quote (thanks by the way) is not easy for me, the FBSD box is a tool for a specific job, I don't use it as a general purpose PC.. All that was some weeks back, and the box has been ticking away to itself now just fine, for 49 days 19hours and 22 minutes it tells me via a remote admin link, as I type this. Best Regards. Dave B.