From owner-freebsd-geom@FreeBSD.ORG Thu Mar 18 19:23:05 2010 Return-Path: Delivered-To: freebsd-geom@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id C6A361065670 for ; Thu, 18 Mar 2010 19:23:05 +0000 (UTC) (envelope-from 000.fbsd@quip.cz) Received: from elsa.codelab.cz (elsa.codelab.cz [94.124.105.4]) by mx1.freebsd.org (Postfix) with ESMTP id 82E968FC29 for ; Thu, 18 Mar 2010 19:23:05 +0000 (UTC) Received: from elsa.codelab.cz (localhost.codelab.cz [127.0.0.1]) by elsa.codelab.cz (Postfix) with ESMTP id 6FBFE19E023 for ; Thu, 18 Mar 2010 20:23:03 +0100 (CET) Received: from [192.168.1.2] (r5bb235.net.upc.cz [86.49.61.235]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by elsa.codelab.cz (Postfix) with ESMTPSA id 24B6419E019 for ; Thu, 18 Mar 2010 20:23:01 +0100 (CET) Message-ID: <4BA27D94.4060508@quip.cz> Date: Thu, 18 Mar 2010 20:23:00 +0100 From: Miroslav Lachman <000.fbsd@quip.cz> User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.9.1.8) Gecko/20100205 SeaMonkey/2.0.3 MIME-Version: 1.0 To: freebsd-geom@FreeBSD.org Content-Type: text/plain; charset=ISO-8859-2; format=flowed Content-Transfer-Encoding: 7bit Cc: Subject: 7.3-RC2 - fdisk cannot write or modify sector zero on gmirror - GEOM bug? X-BeenThere: freebsd-geom@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: GEOM-specific discussions and implementations List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 18 Mar 2010 19:23:05 -0000 I sent this message with subject "Geom not found: "gm0" / Failed to write sector zero" to the freebsd-stable list a week ago, but nobody replied. I did some tests - more on the end of this message. --------------------------------------------------- I just installed 7.3-RC2 amd64 on new server. I created slice s1 (80GB on disk ad4 (500GB), then partitions for system (/, swap, /var, /usr, /tmp) by sysinstall. After base install I created gmirror gm0 as usual (I did it many times). Now I am no longer in datacenter and have only ssh access to this server and I need to create slice s2 with some partitions for data storage, but fdisk failed. fdisk -u /dev/mirror/gm0 At the end, I got this error: Should we write new partition table? [n] y fdisk: Geom not found: "gm0" fdisk: Failed to write sector zero Fdisk failed even if I used sysctl kern.geom.debugflags=16 Question #1 - why 'Geom not found: "gm0"'? Question #2 - is there any way to create slices + partitions on unused space if system is booted from this device? Or is the only way to boot it from some LiveFS / fixit? I found the same question on this list, but without reply http://lists.freebsd.org/pipermail/freebsd-stable/2009-June/050855.html I hope somebody can help / explain it. --------------------------------------------------- Some newer tests. Today I tried it with 7.2 RELEASE under QEMU without gmirror and there is not any problem to write sector zero on to /dev/ad0 I can resize ad0s1 by fdisk with sysctl kern.geom.debugflags=16 (system is booted from ad0s1a) and I can create ad0s2 without any problem. But this is impossible on gmirror with 7.3-RC2. It seems as some bug in GEOM / gmirror for me. Can somebody with GEOM knowledge take a look at it? Miroslav Lachman