From owner-freebsd-geom@FreeBSD.ORG Fri Sep 15 09:45:47 2006 Return-Path: X-Original-To: freebsd-geom@FreeBSD.ORG Delivered-To: freebsd-geom@FreeBSD.ORG Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 3E9F516A40F for ; Fri, 15 Sep 2006 09:45:47 +0000 (UTC) (envelope-from olli@lurza.secnetix.de) Received: from lurza.secnetix.de (lurza.secnetix.de [83.120.8.8]) by mx1.FreeBSD.org (Postfix) with ESMTP id 2B3D543D45 for ; Fri, 15 Sep 2006 09:45:45 +0000 (GMT) (envelope-from olli@lurza.secnetix.de) Received: from lurza.secnetix.de (varonk@localhost [127.0.0.1]) by lurza.secnetix.de (8.13.4/8.13.4) with ESMTP id k8F9jdWe007298 for ; Fri, 15 Sep 2006 11:45:44 +0200 (CEST) (envelope-from oliver.fromme@secnetix.de) Received: (from olli@localhost) by lurza.secnetix.de (8.13.4/8.13.1/Submit) id k8F9jdU6007297; Fri, 15 Sep 2006 11:45:39 +0200 (CEST) (envelope-from olli) Date: Fri, 15 Sep 2006 11:45:39 +0200 (CEST) Message-Id: <200609150945.k8F9jdU6007297@lurza.secnetix.de> From: Oliver Fromme To: freebsd-geom@FreeBSD.ORG In-Reply-To: <20060915090514.90093.qmail@web30314.mail.mud.yahoo.com> X-Newsgroups: list.freebsd-geom User-Agent: tin/1.8.0-20051224 ("Ronay") (UNIX) (FreeBSD/4.11-STABLE (i386)) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-2.1.2 (lurza.secnetix.de [127.0.0.1]); Fri, 15 Sep 2006 11:45:44 +0200 (CEST) Cc: Subject: Re: gmirror size question X-BeenThere: freebsd-geom@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: freebsd-geom@FreeBSD.ORG List-Id: GEOM-specific discussions and implementations List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 15 Sep 2006 09:45:47 -0000 R. B. Riddick wrote: > Oliver Fromme wrote: > > PS: I think that hint should be mentioned in the Handbook > > section about gmirror. It could prevent major foot-shoting. > > Comments? > > > Hmm... > > I would say, if one buys a new disk, that is 1 sector too short *giggle*, one > could still try the following plan: > 0. single user mode > 1. Make a new file system on the shorter&new disk > 2. Move the data from the old disk to the new disk (MBR with dd, the rest with > cpio or so) > 3. Create a new gmirror just with the new disk as the only disk > 4. Add the old disk to the new gmirror > 5. Change the configuration in order to reflect the changed name of the > gmirror. > QEF (reboot inbetween whenever it seems necessary) Yes, but that takes quite a lot of work and time. If you use RAID1, you don't want any downtime in the first place. Also, it might not be obvious to the person repairing the mirror that the new disk is too small. The EINVAL errno code isn't really very verbose about the root of the problem. If you use the gnop trick at the beginning, so the gmirror is somewhat smaller, then you can simply plug in the new drive, gmirror insert, and you're done. No downtime at all. You don't even have to remember anything special. Best regards Oliver -- Oliver Fromme, secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing Dienstleistungen mit Schwerpunkt FreeBSD: http://www.secnetix.de/bsd Any opinions expressed in this message may be personal to the author and may not necessarily reflect the opinions of secnetix in any way. "[...] one observation we can make here is that Python makes an excellent pseudocoding language, with the wonderful attribute that it can actually be executed." -- Bruce Eckel