From owner-freebsd-stable@FreeBSD.ORG Fri Dec 9 13:55:37 2005 Return-Path: X-Original-To: stable@freebsd.org Delivered-To: freebsd-stable@FreeBSD.ORG Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 195C116A41F for ; Fri, 9 Dec 2005 13:55:37 +0000 (GMT) (envelope-from ivoras@fer.hr) Received: from pinus.cc.fer.hr (pinus.cc.fer.hr [161.53.73.18]) by mx1.FreeBSD.org (Postfix) with ESMTP id 9FDEA43D81 for ; Fri, 9 Dec 2005 13:55:30 +0000 (GMT) (envelope-from ivoras@fer.hr) Received: from [161.53.72.113] (lara.cc.fer.hr [161.53.72.113]) by pinus.cc.fer.hr (8.12.2/8.12.2) with ESMTP id jB9DtNFx013724; Fri, 9 Dec 2005 14:55:24 +0100 (MET) Message-ID: <43998C95.3050505@fer.hr> Date: Fri, 09 Dec 2005 14:54:29 +0100 From: Ivan Voras User-Agent: Mozilla Thunderbird 1.0.6 (X11/20050921) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Michael Schuh References: <1dbad3150512090509l2ab08e03k@mail.gmail.com> In-Reply-To: <1dbad3150512090509l2ab08e03k@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: stable@freebsd.org Subject: Re: Questions about geom-gate and RAID1/10 and CARP X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 09 Dec 2005 13:55:37 -0000 Michael Schuh wrote: > i have searched informations about geom-gate and RAID1 or > Raid10 over TCP/IP. But nothing relevant found, so that i write > the questions here. Actually, there has been some discussion about this, but you probably won't like the result... > Has anyone any experiences with geom-gate and doing RAID1 or RAID10 over > TCP/IP? And has anyone a good solution in Production use? Theoretically, yes - it can be done this way. You could use any GEOM-aware RAID solution, and throw ggate in the mix. When I tried it (back in early 5-stable days) I could create the setup just fine, but could not stabilise it - gmirror kept loosing the ggate component(s), possibly(?) due to timeouts from network latency. IIRC, just around the time 6-stable was branched there was a similar report from somebody else. BUT, ggate has had several changes since then that should address performace, so maybe it's time to try again. There's another problem: if you do get the over-the-network mirroring to work, you won't be able to share data this way: the one-writer-multiple-readers scenario won't work because the filesystem doesn't support it on the reader side (when the data gets modified by the writer, the reader doesn't know about it). Readonly-for-all scenario will work. (see also this: http://docs.freebsd.org/cgi/mid.cgi?438B05D6.3000108 - I'll maybe find the time soon)