From owner-freebsd-questions@FreeBSD.ORG Wed Aug 11 05:05:32 2010 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 1EA881065670 for ; Wed, 11 Aug 2010 05:05:32 +0000 (UTC) (envelope-from dick@nagual.nl) Received: from mail.nagual.nl (cc535223-a.groni1.gr.home.nl [82.73.72.175]) by mx1.freebsd.org (Postfix) with ESMTP id 8E9FF8FC1F for ; Wed, 11 Aug 2010 05:05:31 +0000 (UTC) Received: from [192.168.11.34] [192.168.11.34] by arwen (Axigen) with (AES256-SHA encrypted) ESMTPSA id 0F3095; Wed, 11 Aug 2010 07:07:15 +0200 Message-ID: <4C622FA2.9050504@nagual.nl> Date: Wed, 11 Aug 2010 07:05:38 +0200 From: Dick Hoogendijk User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; nl; rv:1.9.2.8) Gecko/20100802 Thunderbird/3.1.2 MIME-Version: 1.0 To: freebsd-questions@freebsd.org References: <4C61B215.9030603@nagual.nl> <01FB8F39BAD0BD49A6D0DA8F7897392904F7BD@Mercury.galaxy.lan.lcl> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: quoted-printable X-AxigenSpam-Level: 4 Subject: Re: ZFS woes 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: Wed, 11 Aug 2010 05:05:32 -0000 On 11-8-2010 0:52, Dale Scott wrote: >>> wiped out the firt mb; i used sysinstall to create a fbsd slice; wipe= d >>> it out again; booted knoppix to create an EFI / GPT; booted into >>> opensolaris and created a zpool (v14), but nothing, nothing=20 >>> did the trick. > I was doing a vanilla fbsd install recently using a couple re-claimed 2= 50GB IDE drives. The install completed without errors, but after reboot G= EOM complained bitterly about the secondary GPT table on the boot drive b= eing corrupted or invalid, and unrecoverable corrupted or invalid GPT tab= les on the 2nd drive. By trying something like above, I was able to get t= he system drive to rebuild the secondary GPT table, but nothing worked on= the second drive. Google told me a targeted approach was technically pos= sible (by calculating exactly where a specific drive stores its GPT metad= ata and zeroing just that bit), but also that the broader solution of zer= oing out the entire drive would be faster for me than figuring out the ca= lculation (about 18 hrs to zero the entire drive, at least it was mostly = while sleeping): "dd if=3D/dev/zero of=3D/dev/ad3 bs=3D64K" (no idea if t= he block size is optimal or even relevant). I did not want to overwrite two drives with /dev/zero, so I created a=20 mirror with gmirror yesterday, folowing the steps from the freebsd manual= =2E After it was completed I just did: # gmirror stop gm0 # gmirror clear /dev/ad12 # gmirror clear /dev/ad14 # dd if=3D/dev/zero of=3D/dev/ad12 bs=3D1m count=3D1 # dd if=3D/dev/zero of=3D/dev/ad14 bs=3D1m count=3D1 # kldload zfs # zpool create store mirror ad12 ad14 ## Wrote some data to /store ## # zpool scrub store # zpool history store ## No More Errors !!! ## I guess creating the gmirror metadata / mirror and removing it cleared=20 all data which caused me so much trouble. I happely removed the geom_mirror_load=3D"YES" with zfs_load=3D"YES" and = have what I wanted: FreeBSD/zfs