From owner-freebsd-fs@FreeBSD.ORG Sun Apr 22 03:44:08 2007 Return-Path: X-Original-To: freebsd-fs@freebsd.org Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 8C83B16A403 for ; Sun, 22 Apr 2007 03:44:08 +0000 (UTC) (envelope-from anderson@freebsd.org) Received: from mh2.centtech.com (moat3.centtech.com [64.129.166.50]) by mx1.freebsd.org (Postfix) with ESMTP id 5E07913C43E for ; Sun, 22 Apr 2007 03:44:08 +0000 (UTC) (envelope-from anderson@freebsd.org) Received: from neutrino.centtech.com (andersonbox1.centtech.com [192.168.42.21]) by mh2.centtech.com (8.13.8/8.13.8) with ESMTP id l3M3i32H019075; Sat, 21 Apr 2007 22:44:04 -0500 (CDT) (envelope-from anderson@freebsd.org) Message-ID: <462ADA03.6090406@freebsd.org> Date: Sat, 21 Apr 2007 22:44:03 -0500 From: Eric Anderson User-Agent: Thunderbird 2.0.0.0 (X11/20070420) MIME-Version: 1.0 To: ticso@cicely.de References: <20070420232209.G4559@nux.eros.office> <20070421000029.N4559@nux.eros.office> <20070421000805.GA64413@cicely12.cicely.de> <20070421011716.B4559@nux.eros.office> <20070421010734.GD64413@cicely12.cicely.de> <20070421021529.R16230@nux.eros.office> <4629711B.9070902@freebsd.org> <20070421100233.GE64413@cicely12.cicely.de> In-Reply-To: <20070421100233.GE64413@cicely12.cicely.de> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: ClamAV 0.88.4/3146/Sat Apr 21 14:39:19 2007 on mh2.centtech.com X-Virus-Status: Clean X-Spam-Status: No, score=-1.9 required=8.0 tests=AWL,BAYES_00 autolearn=ham version=3.1.6 X-Spam-Checker-Version: SpamAssassin 3.1.6 (2006-10-03) on mh2.centtech.com Cc: freebsd-fs@freebsd.org, Mike Wolman Subject: Re: lazy mirror / live backup X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 22 Apr 2007 03:44:08 -0000 On 04/21/07 05:02, Bernd Walter wrote: > On Fri, Apr 20, 2007 at 09:04:11PM -0500, Eric Anderson wrote: >> On 04/20/07 20:25, Mike Wolman wrote: >>> On Sat, 21 Apr 2007, Bernd Walter wrote: >>> >>>> On Sat, Apr 21, 2007 at 01:38:31AM +0100, Mike Wolman wrote: >>> Yea i use rsync and snapshots quite a bit, but unfortunately rsync works >>> at the filesystem level so you cant really get a bootable image of the >>> whole device. It would be nice if this could be done without user >>> interaction, ie if the ggatec component of a mirror disappears and >>> reappears gmirror justs gets to work syncing things up. >> rsync and it's like are great tools, but traversing the tree every time >> is not only slow and heavy handed, but it takes an enormous amount of >> memory (akin to fsck) for large file systems. rsync isn't the right >> tool for lazy syncing. > > Thich file tree? > I was talking about a snapshot, which is a single file. > Oh, I didn't realize you were recommending rsync'ing the snapshot file itself. Wow. That seems pretty brutal of a solution to me. The only gain is the reduced data transferred over the net, and not the quicker sync time, less load on your source disks, etc. I think everyone knows that there are some solutions to the problem. The problem is they are not good or elegant solutions. What Mike is proposing is an elegant solution, that is slick and smooth, and simple. Eric