From owner-freebsd-questions@FreeBSD.ORG  Thu Jul 12 16:07:27 2012
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 37A0E106564A
	for <freebsd-questions@freebsd.org>;
	Thu, 12 Jul 2012 16:07:27 +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 E38C58FC08
	for <freebsd-questions@freebsd.org>;
	Thu, 12 Jul 2012 16:07:26 +0000 (UTC)
Received: from wonkity.com (localhost [127.0.0.1])
	by wonkity.com (8.14.5/8.14.5) with ESMTP id q6CG7Q8X047562;
	Thu, 12 Jul 2012 10:07:26 -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 q6CG7Qpe047559;
	Thu, 12 Jul 2012 10:07:26 -0600 (MDT)
	(envelope-from wblock@wonkity.com)
Date: Thu, 12 Jul 2012 10:07:26 -0600 (MDT)
From: Warren Block <wblock@wonkity.com>
To: Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl>
In-Reply-To: <alpine.BSF.2.00.1207121649080.2235@wojtek.tensor.gdynia.pl>
Message-ID: <alpine.BSF.2.00.1207121004560.47013@wonkity.com>
References: <CAGpP9XOvVor7HmxDP7SFhc7AFnpSf-s+gXbkJsguiAo=xNvnVA@mail.gmail.com>
	<CAPj0R5L1=HaY1Bf-51FB59J6Q4pX1s4yDbzXoAAWRwei6yqt-A@mail.gmail.com>
	<alpine.BSF.2.00.1207110702490.76348@wonkity.com>
	<alpine.BSF.2.00.1207121649080.2235@wojtek.tensor.gdynia.pl>
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, 12 Jul 2012 10:07:26 -0600 (MDT)
Cc: Kaya Saman <kayasaman@gmail.com>, miles kuo <miles.kuo@gmail.com>,
	freebsd-questions@freebsd.org
Subject: Re: How to mirror the FreeBSD OS on two disks
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: Thu, 12 Jul 2012 16:07:27 -0000

On Thu, 12 Jul 2012, Wojciech Puchar wrote:

>>> 
>>> I am no expert at this however a quick Google search comes up with:
>>> 
>>> http://www.freebsd.org/doc/handbook/geom-mirror.html
>> 
>> The procedure shown there produces a mirror that will not boot on FreeBSD 
>> 9.
>
> no idea but my procedure certainly would work if you use installer
>
> 1) install to first disk
> 2) gmirror label system /dev/seconddisk
> 3) bsdlabel -w /dev/mirror/system
> 4) bsdlabel -e /dev/mirror/system - make partitions as required.
> 5) bsdlabel -B /dev/mirror/system
> 6) newfs all created partitions (/dev/mirror/systema etc...)
> 7) add
>
> vfs.root.mountfrom="ufs:mirror/systema"
>
> to loader.conf
>
> edit /etc/fstab and change all things to new places
> 8) mount and copy files using tar or dump/restore to new place
> 9) reboot. system will start from gmirror
> 10) gmirror insert system /dev/firstdisk
>
> all done.
>
> if installer is not used but bootable media with complete system, just create 
> gmirror then as usual.

The current Handbook procedure avoids the copy by using the existing 
disk as-is and just writing the gmirror metadata to the last block.  If 
that last block is already part of an MBR partition, the more strict 
checking stops booting in 9.0.