From owner-freebsd-geom@FreeBSD.ORG  Fri Jul 20 03:50:20 2012
Return-Path: <owner-freebsd-geom@FreeBSD.ORG>
Delivered-To: freebsd-geom@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 38FE7106564A
	for <freebsd-geom@freebsd.org>; Fri, 20 Jul 2012 03:50:20 +0000 (UTC)
	(envelope-from wblock@wonkity.com)
Received: from wonkity.com (wonkity.com [67.158.26.137])
	by mx1.freebsd.org (Postfix) with ESMTP id EA0DA8FC14
	for <freebsd-geom@freebsd.org>; Fri, 20 Jul 2012 03:50:19 +0000 (UTC)
Received: from wonkity.com (localhost [127.0.0.1])
	by wonkity.com (8.14.5/8.14.5) with ESMTP id q6K3oIGM009800;
	Thu, 19 Jul 2012 21:50:18 -0600 (MDT)
	(envelope-from wblock@wonkity.com)
Received: from localhost (wblock@localhost)
	by wonkity.com (8.14.5/8.14.5/Submit) with ESMTP id q6K3oINb009797;
	Thu, 19 Jul 2012 21:50:18 -0600 (MDT)
	(envelope-from wblock@wonkity.com)
Date: Thu, 19 Jul 2012 21:50:18 -0600 (MDT)
From: Warren Block <wblock@wonkity.com>
To: Dave Hayes <dave@jetcafe.org>
In-Reply-To: <500875C2.1070903@jetcafe.org>
Message-ID: <alpine.BSF.2.00.1207192144590.9772@wonkity.com>
References: <500875C2.1070903@jetcafe.org>
User-Agent: Alpine 2.00 (BSF 1167 2008-08-23)
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed
X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7
	(wonkity.com [127.0.0.1]); Thu, 19 Jul 2012 21:50:18 -0600 (MDT)
Cc: freebsd-geom@freebsd.org
Subject: Re: Geom, MBR, labels, and usb sticks
X-BeenThere: freebsd-geom@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: GEOM-specific discussions and implementations
	<freebsd-geom.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-geom>,
	<mailto:freebsd-geom-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-geom>
List-Post: <mailto:freebsd-geom@freebsd.org>
List-Help: <mailto:freebsd-geom-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-geom>,
	<mailto:freebsd-geom-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Fri, 20 Jul 2012 03:50:20 -0000

On Thu, 19 Jul 2012, Dave Hayes wrote:

> # gpart show da0s2
> =>       0  15567804  da0s2  BSD  (7.4G)
>          0        16      2  freebsd-ufs  (8.0k)
>         16  15567788      1  freebsd-ufs  (7.4G)
>
> Now I want to label the partition da0s2a. From the documentation in the man 
> pages, I seem to be being told that
>
> # gpart modify -l foo -i 1 da0s2a
>
> will not work, and it doesn't:
>
> gpart: Invalid argument

No, gpart's labels are for GPT partitions.

> So let's try newfs:
>
> # newfs -L foo /dev/da0s2a
> ...
> # gpart show -l da0s2
> =>       0  15567804  da0s2  BSD  (7.4G)
>          0        16      2  (null)  (8.0k)
>         16  15567788      1  (null)  (7.4G)
>
> and still the labels do not show up.

They won't show in gpart because they are filesystem labels.  They will 
show in 'tunefs -p' or 'file -s'.

> I really do want to be able to mount 
> /dev/ufs/foo as the root device, but as I understand things if gpart doesn't 
> show the label then the glabel subsystem won't set up the proper device file.
>
> What gives here? Am I missing something important?

There is more than one type of label.  glabel(8) has a list that 
includes the device directory where the label appears.