From owner-freebsd-fs@freebsd.org Wed Aug 17 09:03:03 2016 Return-Path: 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 5827BBBC081 for ; Wed, 17 Aug 2016 09:03:03 +0000 (UTC) (envelope-from juergen.gotteswinter@internetx.com) Received: from mx1.internetx.com (mx1.internetx.com [62.116.129.39]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 050BF1B18 for ; Wed, 17 Aug 2016 09:03:02 +0000 (UTC) (envelope-from juergen.gotteswinter@internetx.com) Received: from localhost (localhost [127.0.0.1]) by mx1.internetx.com (Postfix) with ESMTP id D9EDB4C4C89E; Wed, 17 Aug 2016 11:02:59 +0200 (CEST) X-Virus-Scanned: InterNetX GmbH amavisd-new at ix-mailer.internetx.de Received: from mx1.internetx.com ([62.116.129.39]) by localhost (ix-mailer.internetx.de [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id gqFxgZu8qn7T; Wed, 17 Aug 2016 11:02:57 +0200 (CEST) Received: from [192.168.100.26] (pizza.internetx.de [62.116.129.3]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by mx1.internetx.com (Postfix) with ESMTPSA id E05084C4C89D; Wed, 17 Aug 2016 11:02:57 +0200 (CEST) Reply-To: juergen.gotteswinter@internetx.com Subject: Re: HAST + ZFS + NFS + CARP References: <6035AB85-8E62-4F0A-9FA8-125B31A7A387@gmail.com> <20160703192945.GE41276@mordor.lan> <20160703214723.GF41276@mordor.lan> <65906F84-CFFC-40E9-8236-56AFB6BE2DE1@ixsystems.com> <61283600-A41A-4A8A-92F9-7FAFF54DD175@ixsystems.com> <20160704183643.GI41276@mordor.lan> <20160704193131.GJ41276@mordor.lan> <20160811091016.GI70364@mordor.lan> <1AA52221-9B04-4CF6-97A3-D2C2B330B7F9@sarenet.es> <472bc879-977f-8c4c-c91a-84cc61efcd86@internetx.com> <1AE36A3B-A2BA-47D2-A872-1E7E9EFA201D@sarenet.es> To: Borja Marcos Cc: freebsd-fs@freebsd.org From: InterNetX - Juergen Gotteswinter Organization: InterNetX GmbH Message-ID: Date: Wed, 17 Aug 2016 11:02:57 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: <1AE36A3B-A2BA-47D2-A872-1E7E9EFA201D@sarenet.es> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 17 Aug 2016 09:03:03 -0000 Am 17.08.2016 um 10:53 schrieb Borja Marcos: > >> On 17 Aug 2016, at 09:25, InterNetX - Juergen Gotteswinter wrote: >> try dual split import :D i mean, zpool -f import on 2 machines hooked up >> to the same disk chassis. >> >> kaboom, really ugly kaboom. thats what is very likely to happen sooner >> or later especially when it comes to homegrown automatism solutions. >> even the commercial parts where much more time/work goes into such >> solutions fail in a regular manner > > Well, don’t expect to father children after shooting your balls! ;) > > I am not a big fan of such closely coupled solutions. There are quite > some failure modes that can break such a configuration, not just a brainless > “dual split import” as you say :) > > Misbehaving software (read, a ZFS bug) can render the pool unusable and, no matter how many > redundant servers you have connected to your chassis, you are toast. Using incremental replication > over a network is much more robust, and it offers a lot of fault isolation. Moreover, you can place the > servers in different buildings, etc. in my case it was caused by rsf-1 cluster software > > Networks even offer a more than reasonable protection from electrical problems. Especially if you get > paranoid and use fiber, in which case protection is absolute. > > > > Borja. >