From owner-freebsd-geom@FreeBSD.ORG Wed Feb 7 21:36:42 2007 Return-Path: X-Original-To: freebsd-geom@freebsd.org Delivered-To: freebsd-geom@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 9CBB516A400 for ; Wed, 7 Feb 2007 21:36:42 +0000 (UTC) (envelope-from simon@zaphod.nitro.dk) Received: from mx.nitro.dk (zarniwoop.nitro.dk [83.92.207.38]) by mx1.freebsd.org (Postfix) with ESMTP id 57E1F13C481 for ; Wed, 7 Feb 2007 21:36:41 +0000 (UTC) (envelope-from simon@zaphod.nitro.dk) Received: from zaphod.nitro.dk (unknown [192.168.3.39]) by mx.nitro.dk (Postfix) with ESMTP id 18C032D7A0C; Wed, 7 Feb 2007 21:36:07 +0000 (UTC) Received: by zaphod.nitro.dk (Postfix, from userid 3000) id E0E181141D; Wed, 7 Feb 2007 22:36:40 +0100 (CET) Date: Wed, 7 Feb 2007 22:36:40 +0100 From: "Simon L. Nielsen" To: Ivan Voras Message-ID: <20070207213640.GB988@zaphod.nitro.dk> References: <45C98F32.20308@enderzone.com> <99017.1170839681@critter.freebsd.dk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.11 Cc: freebsd-geom@freebsd.org Subject: Re: New g_part class 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: Wed, 07 Feb 2007 21:36:42 -0000 On 2007.02.07 22:16:38 +0100, Ivan Voras wrote: > Poul-Henning Kamp wrote: > > > You mean writing to sectors which mounted filesystems belive they > > have exclusive use of ? > > > > No, GEOM doesn't support or allow that. > > Ok, the need for sysctl kern.geom.debugflags=16 arises because the live > system to be used as master has mounted partitions, and those partitions > span the whole disk, thus conflict with gmirror which wants to use the > last sector. Since using the last sector for metadata is The Official > Way, how about making such conflicts easy to avoid, like for example > building additional logic in g_part to create partitions one sector > smaller than the container? Eh, gmirror already does the right thing... : [root@eddie:simon] gmirror status gmd0 Name Status Components mirror/gmd0 COMPLETE ad18 ad20 [root@eddie:simon] diskinfo -v /dev/mirror/gmd0 /dev/mirror/gmd0 512 # sectorsize 200049647104 # mediasize in bytes (186G) 390721967 # mediasize in sectors [root@eddie:simon] diskinfo -v /dev/ad18 /dev/ad18 512 # sectorsize 200049647616 # mediasize in bytes (186G) 390721968 # mediasize in sectors 387621 # Cylinders according to firmware. 16 # Heads according to firmware. 63 # Sectors according to firmware. IE. the gmirror device is one sector smaller than the disk device. -- Simon L. Nielsen