From owner-freebsd-questions@FreeBSD.ORG  Wed May 12 11:12:09 2010
Return-Path: <owner-freebsd-questions@FreeBSD.ORG>
Delivered-To: freebsd-questions@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52])
	by hub.freebsd.org (Postfix) with ESMTP id CA465106566B
	for <freebsd-questions@freebsd.org>;
	Wed, 12 May 2010 11:12:09 +0000 (UTC)
	(envelope-from ahamiltonwright@mta.ca)
Received: from smtpx.mta.ca (smtpx.mta.ca [138.73.1.138])
	by mx1.freebsd.org (Postfix) with ESMTP id 9B16E8FC19
	for <freebsd-questions@freebsd.org>;
	Wed, 12 May 2010 11:12:09 +0000 (UTC)
Received: from [138.73.29.51] (port=49173 helo=qemg.org)
	by smtpx.mta.ca with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.71)
	(envelope-from <ahamiltonwright@mta.ca>)
	id 1OC9rB-0001I1-Rp; Wed, 12 May 2010 08:12:05 -0300
Date: Wed, 12 May 2010 08:12:05 -0300 (ADT)
From: "A. Wright" <andrew@qemg.org>
To: Jon Theil Nielsen <jontheil@gmail.com>
In-Reply-To: <AANLkTil9Xey43nDf130e_RRE3ZNsI1RQwrp-B9XPTqBr@mail.gmail.com>
Message-ID: <alpine.BSF.2.00.1005120807230.64303@qemg.org>
References: <y2z8f82c35c1004301044pd7168618qa23eb66438350a5d@mail.gmail.com>
	<4BDC794B.2060009@cam.ac.uk>
	<q2s8f82c35c1005011910w1ad4792ehd90f38d3a8883519@mail.gmail.com>
	<4BDDBED0.7040504@cam.ac.uk>
	<AANLkTil9Xey43nDf130e_RRE3ZNsI1RQwrp-B9XPTqBr@mail.gmail.com>
User-Agent: Alpine 2.00 (BSF 1167 2008-08-23)
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed
Sender: ahamiltonwright@mta.ca
Cc: User Questions <freebsd-questions@freebsd.org>,
	Christopher Key <cjk32@cam.ac.uk>
Subject: Re: More than 8 partitions
X-BeenThere: freebsd-questions@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: User questions <freebsd-questions.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-questions>, 
	<mailto:freebsd-questions-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-questions>
List-Post: <mailto:freebsd-questions@freebsd.org>
List-Help: <mailto:freebsd-questions-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-questions>, 
	<mailto:freebsd-questions-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Wed, 12 May 2010 11:12:09 -0000



> On 2010/5/2, Christopher Key <cjk32@cam.ac.uk> wrote:
>
>> frhed.  Next write the data back to the disk:
>>
>> dd if=/tmp/hdr of=/dev/da0s2


On 2010/5/12, Jon Theil Nielsen wrote:

> obviously this is not the case. So I'll dd the existing partitions to
> another drive, use gpart to create "enough" partitions and then dd the old
> content back. I could easily use a standard disk layout, but the other
> approach will add some to my FreeBSD knowledge..


Just pointing out a rabbit hole here . . .

You should be aware, too that if you want to _change_ the size
(or any of several other params) of the filesystem, you don't
really want dd, you want to dump(8) the filesystem and then use
restore(8) -- as the man page says, this is the only reliable
way to change various filesystem params.

Using dd will be fine only if the sizes and all other params are
to be identical (which is the case in Chris' comment, but not in
the general case).

Andrew.