From owner-freebsd-fs@freebsd.org  Thu Oct 29 02:33:21 2015
Return-Path: <owner-freebsd-fs@freebsd.org>
Delivered-To: freebsd-fs@mailman.ysv.freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 by mailman.ysv.freebsd.org (Postfix) with ESMTP id 530578236
 for <freebsd-fs@mailman.ysv.freebsd.org>; Thu, 29 Oct 2015 02:33:21 +0000 (UTC)
 (envelope-from pmurray@nevada.net.nz)
Received: from mailman.ysv.freebsd.org (mailman.ysv.freebsd.org
 [IPv6:2001:1900:2254:206a::50:5])
 by mx1.freebsd.org (Postfix) with ESMTP id 3D0881860
 for <freebsd-fs@freebsd.org>; Thu, 29 Oct 2015 02:33:21 +0000 (UTC)
 (envelope-from pmurray@nevada.net.nz)
Received: by mailman.ysv.freebsd.org (Postfix)
 id 3C69D8235; Thu, 29 Oct 2015 02:33:21 +0000 (UTC)
Delivered-To: fs@mailman.ysv.freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 by mailman.ysv.freebsd.org (Postfix) with ESMTP id 3C07C8232
 for <fs@mailman.ysv.freebsd.org>; Thu, 29 Oct 2015 02:33:21 +0000 (UTC)
 (envelope-from pmurray@nevada.net.nz)
Received: from bellagio.open2view.net (bellagio.open2view.net [210.48.79.75])
 (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits))
 (Client did not present a certificate)
 by mx1.freebsd.org (Postfix) with ESMTPS id 0B43B185E
 for <fs@freebsd.org>; Thu, 29 Oct 2015 02:33:20 +0000 (UTC)
 (envelope-from pmurray@nevada.net.nz)
Received: from dhcp100.akl.open2view.lan (unknown [114.23.246.97])
 (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits))
 (No client certificate requested)
 (Authenticated sender: pmurray@nevada.net.nz)
 by bellagio.open2view.net (Postfix) with ESMTPSA id 89DBC12AA584;
 Thu, 29 Oct 2015 15:26:57 +1300 (NZDT)
Content-Type: text/plain; charset=utf-8
Mime-Version: 1.0 (Mac OS X Mail 9.1 \(3096.5\))
Subject: Re: iSCSI/ZFS strangeness
From: Philip Murray <pmurray@nevada.net.nz>
In-Reply-To: <20151029015721.GA95057@mail.michaelwlucas.com>
Date: Thu, 29 Oct 2015 15:26:57 +1300
Cc: fs@freebsd.org
Content-Transfer-Encoding: quoted-printable
Message-Id: <B09FE8F0-F463-44C9-896C-CA55305113CE@nevada.net.nz>
References: <20151029015721.GA95057@mail.michaelwlucas.com>
To: "Michael W. Lucas" <mwlucas@michaelwlucas.com>
X-Mailer: Apple Mail (2.3096.5)
X-BeenThere: freebsd-fs@freebsd.org
X-Mailman-Version: 2.1.20
Precedence: list
List-Id: Filesystems <freebsd-fs.freebsd.org>
List-Unsubscribe: <https://lists.freebsd.org/mailman/options/freebsd-fs>,
 <mailto:freebsd-fs-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-fs/>
List-Post: <mailto:freebsd-fs@freebsd.org>
List-Help: <mailto:freebsd-fs-request@freebsd.org?subject=help>
List-Subscribe: <https://lists.freebsd.org/mailman/listinfo/freebsd-fs>,
 <mailto:freebsd-fs-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 29 Oct 2015 02:33:21 -0000


> On 29/10/2015, at 2:57 PM, Michael W. Lucas =
<mwlucas@michaelwlucas.com> wrote:
>=20
> Hi,
>=20
> I'm experimenting with iSCSI HA with FreeBSD 10.2 amd64. I know people
> do this sort of thing, but I can't figure out what I'm missing. (Most
> of the tutorials cover HAST instead). I suspect the real problem is
> "Lucas doesn't know the right search terms."
>=20
> The goal is to make an iSCSI-based ZFS pool that's available to two
> separate hosts, and remains available even if one of the iSCSI servers
> fails. Instead, the pool hangs when either of the iSCSI servers goes
> down.

I=E2=80=99m no expert and have never used iSCSI and FreeBSD before, but =
I think you might=20
want to look at the kern.iscsi.fail_on_disconnection sysctl.

man 4 iscsi

That means the devices will fail instead of hang, and ZFS might decide =
to mark those=20
devices as faulted instead of waiting for them to respond.

Cheers

Phil=