From owner-freebsd-hackers@FreeBSD.ORG Tue Sep 30 11:23:26 2014 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 426FEE72 for ; Tue, 30 Sep 2014 11:23:26 +0000 (UTC) Received: from puchar.net (puchar.net [188.252.31.250]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "puchar.net", Issuer "puchar.net" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id C3DD9A15 for ; Tue, 30 Sep 2014 11:23:25 +0000 (UTC) Received: Received: from 127.0.0.1 (localhost [127.0.0.1]) by puchar.net (8.14.9/8.14.9) with ESMTP id s8UB4XBN001014; Tue, 30 Sep 2014 13:04:35 +0200 (CEST) (envelope-from wojtek@puchar.net) Date: Tue, 30 Sep 2014 13:04:34 +0200 (CEST) From: Wojciech Puchar X-X-Sender: wojtek@laptop To: mexas@bristol.ac.uk Subject: Re: cluster FS? In-Reply-To: <201409300845.s8U8jUTa079241@mech-as221.men.bris.ac.uk> Message-ID: References: <201409300845.s8U8jUTa079241@mech-as221.men.bris.ac.uk> User-Agent: Alpine 2.00 (BSF 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.4.3 (puchar.net [10.0.1.1]); Tue, 30 Sep 2014 13:04:35 +0200 (CEST) Cc: freebsd-hackers@freebsd.org X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 30 Sep 2014 11:23:26 -0000 > > It seems to me (just from reading the handbook) > that none of NFS, HAST or iSCSI provide this. none of following are filesystems at all. NFS is remote access to filesystem, the rest presents raw block device. > My specific needs are as follows. > I have multiple nodes and a disk array. > Each node is connected by fibre to the disk array. > I want to have each node read/write access > to all disks on disk array. > So that if any node fails, the > data is still accessible > via the remaining nodes. as disk array presents block devices, not files it is not possible to have filesystem read write access with more than one computer to the same block device. There is no AFAIK filesystems that can communicate between nodes to synchronize state after writes and prevent conflict. > I want to have all nodes equal, i.e. no master/slave > or server/client model. Also, the disk array > provides adequate RAID already, so that is not instead of using disk arrays (expensive) it's better to run FreeBSD as file server with good deal of disks and connectivity and export filesystems using eg. NFS. you may do any RAID type and any filesystem not only cheaper but with extra security - on disk format is known and open and you may access these disks with any other computer running FreeBSD.