From owner-freebsd-current@FreeBSD.ORG Mon Feb 2 19:46:19 2009 Return-Path: Delivered-To: current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id D644110657AD for ; Mon, 2 Feb 2009 19:46:18 +0000 (UTC) (envelope-from dimitry@andric.com) Received: from springbank.echomania.com (springbank.echomania.com [82.94.255.114]) by mx1.freebsd.org (Postfix) with ESMTP id 902158FC1F for ; Mon, 2 Feb 2009 19:46:18 +0000 (UTC) (envelope-from dimitry@andric.com) Received: from localhost (localhost [127.0.0.1]) by springbank.echomania.com (Postfix) with ESMTP id 07DE7A7087; Mon, 2 Feb 2009 20:27:39 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at springbank.echomania.com Received: from springbank.echomania.com ([127.0.0.1]) by localhost (springbank.echomania.com [127.0.0.1]) (amavisd-new, port 10024) with LMTP id ye0aN5IioCCI; Mon, 2 Feb 2009 20:27:28 +0100 (CET) Received: from [87.251.56.140] (tensor.andric.com [87.251.56.140]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by springbank.echomania.com (Postfix) with ESMTPSA id A0A22A707E; Mon, 2 Feb 2009 20:27:28 +0100 (CET) Message-ID: <49874922.5050309@andric.com> Date: Mon, 02 Feb 2009 20:27:30 +0100 From: Dimitry Andric User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.2; en-US; rv:1.9.1b3pre) Gecko/20090129 Shredder/3.0b2pre MIME-Version: 1.0 To: Marcel Moolenaar References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: FreeBSD Current Subject: Re: GEOM_PART: a quick update on logical partitions X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 02 Feb 2009 19:46:22 -0000 On 2009-02-02 20:16, Marcel Moolenaar wrote: > In case people are wondering: I'm working on proper support for > logical partitions. This should also allow us to create and > modify them. Of course when you add or remove a partition, the > index changes and consequently the device name. I still need > to find a good solution for that. Currently I'm thinking that > we should create the device special file that contains the > sector offset (which is the one constant) and create compatibility > symlinks. For example: > > /dev/da0s2.00000000 > /dev/da0s2.0834F7A0 > /dev/da0s5 -> /dev/da0s2.00000000 > /dev/da0s6 -> /dev/da0s2.0834F7A0 > > The idea is that the logical name (i.e. the symlink) change when > you add or remove a partition, but that all references (i.e. mount > information) are against the fixed name. This sector-based ID is a creative approach. :) In Linux, they just assign a GUID to each unique partition (or actually, filesystem), and you can use that to mount it. It doesn't matter anymore whether you shift partitions around then... OTOH, this gives ugly fstabs like: UUID=cf3de368-9729-4399-b612-2b62f4e98930 / ext3 relatime,errors=remount-ro 0 1 Also, you need a place to put the GUID, and there may not be room for this in the filesystem and/or partition.