From owner-freebsd-fs@FreeBSD.ORG Wed Apr 27 10:17:19 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 F09ED106566B for ; Wed, 27 Apr 2011 10:17:19 +0000 (UTC) (envelope-from jdc@koitsu.dyndns.org) Received: from qmta14.emeryville.ca.mail.comcast.net (qmta14.emeryville.ca.mail.comcast.net [76.96.27.212]) by mx1.freebsd.org (Postfix) with ESMTP id D50708FC1A for ; Wed, 27 Apr 2011 10:17:19 +0000 (UTC) Received: from omta05.emeryville.ca.mail.comcast.net ([76.96.30.43]) by qmta14.emeryville.ca.mail.comcast.net with comcast id caE81g0050vp7WLAEaHKdL; Wed, 27 Apr 2011 10:17:19 +0000 Received: from koitsu.dyndns.org ([67.180.84.87]) by omta05.emeryville.ca.mail.comcast.net with comcast id caHJ1g0061t3BNj8RaHJom; Wed, 27 Apr 2011 10:17:19 +0000 Received: by icarus.home.lan (Postfix, from userid 1000) id 3B0F59B418; Wed, 27 Apr 2011 03:17:18 -0700 (PDT) Date: Wed, 27 Apr 2011 03:17:18 -0700 From: Jeremy Chadwick To: Pan Tsu Message-ID: <20110427101718.GA82324@icarus.home.lan> References: <4DB70949.6090104@FreeBSD.org> <20110426182017.GA92471@freebsd.org> <4DB70F13.6060002@FreeBSD.org> <4DB759A1.4050201@FreeBSD.org> <20110427054218.GA88420@DataIX.net> <864o5kgplh.fsf@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <864o5kgplh.fsf@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) Cc: freebsd-fs@freebsd.org, "Jason J. Hellenthal" , dillon@backplane.com 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 10:17:20 -0000 On Wed, Apr 27, 2011 at 10:44:58AM +0400, Pan Tsu wrote: > "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 How is this number generated within DFBSD? I have seen hard disks that have literally no serial number (field is blank, and not space-padded either). Some systems vendors do this. I'm wondering if the generated number is based on a combination of details (ex. device model string + serial number string + total drive capacity in bytes), rather than just pure drive serial number. CC'ing Matt as he probably knows. :-) -- | Jeremy Chadwick jdc@parodius.com | | Parodius Networking http://www.parodius.com/ | | UNIX Systems Administrator Mountain View, CA, USA | | Making life hard for others since 1977. PGP 4BD6C0CB |