From owner-freebsd-hackers@FreeBSD.ORG Wed Dec 1 23:47:37 2004 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id AFE3616A4CE; Wed, 1 Dec 2004 23:47:37 +0000 (GMT) Received: from dan.emsphone.com (dan.emsphone.com [199.67.51.101]) by mx1.FreeBSD.org (Postfix) with ESMTP id 54C8343D31; Wed, 1 Dec 2004 23:47:37 +0000 (GMT) (envelope-from dan@dan.emsphone.com) Received: (from dan@localhost) by dan.emsphone.com (8.13.1/8.13.1) id iB1NlaAD074471; Wed, 1 Dec 2004 17:47:36 -0600 (CST) (envelope-from dan) Date: Wed, 1 Dec 2004 17:47:36 -0600 From: Dan Nelson To: "Jason C. Wells" Message-ID: <20041201234736.GX5518@dan.emsphone.com> References: <41AE3F80.1000506@freebsd.org> <98CE9C0241F1FC59BB8F0547@[192.168.1.16]> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <98CE9C0241F1FC59BB8F0547@[192.168.1.16]> X-OS: FreeBSD 5.3-STABLE X-message-flag: Outlook Error User-Agent: Mutt/1.5.6i cc: hackers@freebsd.org cc: Scott Long cc: current@freebsd.org Subject: Re: My project wish-list for the next 12 months X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 01 Dec 2004 23:47:37 -0000 In the last episode (Dec 01), Jason C. Wells said: > --On Wednesday, December 01, 2004 3:02 PM -0700 Scott Long > wrote: > > >5. Clustered FS support. SANs are all the rage these days, and > >clustered filesystems that allow data to be distributed across many > >storage enpoints and accessed concurrently through the SAN are very > >powerful. RedHat recently bought Sistina and re-opened the GFS source > >code, so exploring this would be very interesting. > > This sounds very close to OpenAFS. I don't know what distinguishes a > SAN from other types of NAS. OpenAFS does everything you mentioned > in the above paragraph. OpenAFS _almost_ works on FreeBSD right now. OpenAFS is a network-centric system that replicates data across its nodes, I think, and each node has a cache. A clustered filesystem uses a single block of shared storage (usually on a fibre-channel SAN, but you can also use shared scsi on a 2-machine cluster) that all servers access directly. The magic is getting the locking right to make sure the servers don't stomp on each other's data. Extremely useful for server farms that need to share large files, or even lots of small files (webservers for example). -- Dan Nelson dnelson@allantgroup.com