From owner-freebsd-fs@FreeBSD.ORG Wed Apr 27 07:08:30 2011 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id E6FA1106566C for ; Wed, 27 Apr 2011 07:08:30 +0000 (UTC) (envelope-from inyaoo@gmail.com) Received: from mail-wy0-f182.google.com (mail-wy0-f182.google.com [74.125.82.182]) by mx1.freebsd.org (Postfix) with ESMTP id 7A0D88FC22 for ; Wed, 27 Apr 2011 07:08:30 +0000 (UTC) Received: by wyf23 with SMTP id 23so1316909wyf.13 for ; Wed, 27 Apr 2011 00:08:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:from:to:cc:subject:references:date:in-reply-to :message-id:user-agent:mime-version:content-type; bh=vQ06J9HnSZC2/UCJgbF+anP31BebyO0noEDCzeGMoE8=; b=TO87UCWu19QigzQ+gBAs3tPIBZzHHeUpfYE8fMX85LI7WPaDaAn8fIWq5ezGgLvunv BcxkEXnnzxNmGggUYVTZtsURdArAirc8qk28VGqrvv+Dfn3vds2HUwPybEVFPSpMVaCV HOkp25ojoNl0jyyDiOelNlaTZ8JzaoztYYTWk= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:references:date:in-reply-to:message-id :user-agent:mime-version:content-type; b=Q9+gjOwI818MP1KquKZ0ERcCeHnvfNtIbU00bRsK45Q3tSQlN7NG6za+WJP7X5vTa/ quxdwxc6JzCGhr1Up8yTGmLnvXArxsMS+CDgcwJptrqNNlsafYqT0HdjNErN2+vPBm+l cBtHVh9avB1yHEIgdXo1vbKdfZ/ISG6Wk4KQg= Received: by 10.227.140.77 with SMTP id h13mr1718733wbu.217.1303886711159; Tue, 26 Apr 2011 23:45:11 -0700 (PDT) Received: from localhost ([87.118.92.174]) by mx.google.com with ESMTPS id p5sm249894wbg.28.2011.04.26.23.45.06 (version=SSLv3 cipher=OTHER); Tue, 26 Apr 2011 23:45:07 -0700 (PDT) From: Pan Tsu To: "Jason J. Hellenthal" References: <4DB70949.6090104@FreeBSD.org> <20110426182017.GA92471@freebsd.org> <4DB70F13.6060002@FreeBSD.org> <4DB759A1.4050201@FreeBSD.org> <20110427054218.GA88420@DataIX.net> Date: Wed, 27 Apr 2011 10:44:58 +0400 In-Reply-To: <20110427054218.GA88420@DataIX.net> (Jason J. Hellenthal's message of "Wed, 27 Apr 2011 01:42:18 -0400") Message-ID: <864o5kgplh.fsf@gmail.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.0.50 (berkeley-unix) MIME-Version: 1.0 Content-Type: text/plain Cc: freebsd-fs@freebsd.org Subject: Re: Why not just name the cam-ata devices the same as the old names? X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 27 Apr 2011 07:08:31 -0000 "Jason J. Hellenthal" writes: > I do not know if this was summed up in a easy way by Jeremy's nice > message below but in short a summary can be made here to clear that up. > > /dev/gptid/* /dev/gpt/* > * These survive its raw partition being newfs'd > * Are only created for disks that are partitioned > and contain a GPT table as can be seen with gpart > show > * Operations on these or the raw partition will not remove them. Not sure if we have support for labels based on disk serial number similar to /dev/serno/* from DragonFlyBSD but /dev/serno/* * no extra step to setup, e.g. `gpart create' or `newfs' * survive wiping entire disk, no metadata stored on-disk * available on every ata disk As CAM_ATA transition goes such labels could be a better choice as they'd lessen the pain when compat naming is gone, e.g. in 10-CURRENT. > The best possible thing you could use here is a GPT scheme for the disks > to remain consistent across newfs's. But relying on GPT for all disks > will not always work in situations where the disk also involves a > operating system that does not support booting off of a GPT disk, like > all of Windows XP and then Win7 for non-Itanium based architectures. Yes > Win7 last checked was said to only support booting GPT schemes on > Itanium systems, so this leaves a lot of systems to only rely on > /dev/ufs*/ labels or generic labels.