From owner-freebsd-stable@FreeBSD.ORG  Mon Jul 21 11:08:39 2008
Return-Path: <owner-freebsd-stable@FreeBSD.ORG>
Delivered-To: freebsd-stable@FreeBSD.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 44599106569E;
	Mon, 21 Jul 2008 11:08:39 +0000 (UTC)
	(envelope-from petefrench@ticketswitch.com)
Received: from constantine.ticketswitch.com (constantine.ticketswitch.com
	[IPv6:2002:57e0:1d4e:1::3])
	by mx1.freebsd.org (Postfix) with ESMTP id E817E8FC0C;
	Mon, 21 Jul 2008 11:08:38 +0000 (UTC)
	(envelope-from petefrench@ticketswitch.com)
Received: from dilbert.rattatosk ([10.64.50.6] helo=dilbert.ticketswitch.com)
	by constantine.ticketswitch.com with esmtps (TLSv1:AES256-SHA:256)
	(Exim 4.69 (FreeBSD)) (envelope-from <petefrench@ticketswitch.com>)
	id 1KKtFs-0007eu-QN; Mon, 21 Jul 2008 12:08:36 +0100
Received: from petefrench by dilbert.ticketswitch.com with local (Exim 4.69
	(FreeBSD)) (envelope-from <petefrench@ticketswitch.com>)
	id 1KKtFs-000J7B-Ow; Mon, 21 Jul 2008 12:08:36 +0100
To: sven@dmv.com
In-Reply-To: <1216304215.14562.19.camel@lanshark.dmv.com>
Message-Id: <E1KKtFs-000J7B-Ow@dilbert.ticketswitch.com>
From: Pete French <petefrench@ticketswitch.com>
Date: Mon, 21 Jul 2008 12:08:36 +0100
Cc: koitsu@FreeBSD.org, freebsd-stable@FreeBSD.org
Subject: Re: Multi-machine mirroring choices
X-BeenThere: freebsd-stable@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Production branch of FreeBSD source code <freebsd-stable.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-stable>, 
	<mailto:freebsd-stable-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-stable>
List-Post: <mailto:freebsd-stable@freebsd.org>
List-Help: <mailto:freebsd-stable-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-stable>,
	<mailto:freebsd-stable-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Mon, 21 Jul 2008 11:08:39 -0000

> The *big* issue I have right now is dealing with the slave machine going
> down. Once the master no longer has a connection to the ggated devices,
> all processes trying to use the device hang in D status. I have tried
> pkill'ing ggatec to no avail and ggatec destroy returns a message of
> gctl being busy. Trying to ggatec destroy -f panics the machine.

Oddly enough, this was the issue I had with iscsi which made me move
to using ggated instead. On our machines I use '-t 10' as an argument to
ggatec, and this makes it timeout once the connection has been down for
a certain amount of time. I am using gmirror on top, not ZFS, and this
handled the drive vanishing from the mirror quite happily. I haven't
tried it with ZFS, which may not like having the device suddenly dissapear.

-pete.