From owner-freebsd-questions@FreeBSD.ORG  Mon Feb  4 23:30:53 2008
Return-Path: <owner-freebsd-questions@FreeBSD.ORG>
Delivered-To: freebsd-questions@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 1EECF16A419
	for <freebsd-questions@freebsd.org>;
	Mon,  4 Feb 2008 23:30:53 +0000 (UTC)
	(envelope-from crapsh@monkeybrains.net)
Received: from ape.monkeybrains.net (ape.monkeybrains.net [208.69.40.11])
	by mx1.freebsd.org (Postfix) with ESMTP id 0F4E713C478
	for <freebsd-questions@freebsd.org>;
	Mon,  4 Feb 2008 23:30:52 +0000 (UTC)
	(envelope-from crapsh@monkeybrains.net)
Received: from [192.168.0.100] (busymonkey.monkeybrains.net [66.92.187.117])
	(authenticated bits=0)
	by ape.monkeybrains.net (8.14.1/8.14.1) with ESMTP id m14NUq0L067272
	(version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO)
	for <freebsd-questions@freebsd.org>;
	Mon, 4 Feb 2008 15:30:52 -0800 (PST)
	(envelope-from crapsh@monkeybrains.net)
Message-ID: <47A7A02C.70206@monkeybrains.net>
Date: Mon, 04 Feb 2008 15:30:52 -0800
From: Rudy Rucker <crapsh@monkeybrains.net>
User-Agent: Thunderbird 1.5.0.10 (X11/20070221)
MIME-Version: 1.0
To: freebsd-questions@freebsd.org
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
X-Virus-Scanned: ClamAV version 0.92,
	clamav-milter version 0.92 on pita.monkeybrains.net
X-Virus-Status: Clean
Subject: If I set up gmirror for a SLICE, how do I set up the MBRs to both
 be bootable?
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: Mon, 04 Feb 2008 23:30:53 -0000


I have two disks, ad0 and ad8.
  ad0s1 and ad8s1 are a gmirror
  ad0s2 and ad8s2 are in a zpool

Other than pulling ad0 and rebooting, is there a set of steps I can take 
to make sure ad8 is bootable?  Is an identical MBR a good enough test?
  dd if=/dev/ad8 of=ad8.mbr bs=512 count=1
  dd if=/dev/ad0 of=ad0.mbr bs=512 count=1
and here are the md5's of the MBR files
  MD5 (ad0.mbr) = f7dced6b4ab7f171cc66ae44ece16a73
  MD5 (ad8.mbr) = f7dced6b4ab7f171cc66ae44ece16a73
I want to check some production boxes to make sure they are set up 
correctly.  I've never had a problem with using whole disks in gmirror, 
but I am new to using gmirror for slices.


Disk setup:

 > gmirror status
         Name    Status  Components
mirror/gm0s1  COMPLETE  ad0s1
                         ad8
 > zpool status
   pool: tank
  state: ONLINE
  scrub: none requested
config:

         NAME        STATE     READ WRITE CKSUM
         tank        ONLINE       0     0     0
           mirror    ONLINE       0     0     0
             ad0s2   ONLINE       0     0     0
             ad8s2   ONLINE       0     0     0

- Rudy