From owner-freebsd-questions@FreeBSD.ORG Sun Sep 5 02:24:13 2004 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 5490016A4CE for ; Sun, 5 Sep 2004 02:24:13 +0000 (GMT) Received: from ganymede.hub.org (blk-222-46-91.eastlink.ca [24.222.46.91]) by mx1.FreeBSD.org (Postfix) with ESMTP id 1E34C43D46 for ; Sun, 5 Sep 2004 02:24:13 +0000 (GMT) (envelope-from scrappy@hub.org) Received: by ganymede.hub.org (Postfix, from userid 1000) id 4CD7D33DAC; Sat, 4 Sep 2004 23:24:14 -0300 (ADT) Received: from localhost (localhost [127.0.0.1]) by ganymede.hub.org (Postfix) with ESMTP id 3B5AE33C96; Sat, 4 Sep 2004 23:24:14 -0300 (ADT) Date: Sat, 4 Sep 2004 23:24:14 -0300 (ADT) From: "Marc G. Fournier" To: Dan Nelson In-Reply-To: <20040905015820.GA44261@dan.emsphone.com> Message-ID: <20040904232130.O812@ganymede.hub.org> References: <20040904222712.F812@ganymede.hub.org> <20040905015820.GA44261@dan.emsphone.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed cc: freebsd-questions@freebsd.org Subject: Re: File system replication between servers X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 05 Sep 2004 02:24:13 -0000 On Sat, 4 Sep 2004, Dan Nelson wrote: > In the last episode (Sep 04), Marc G. Fournier said: >> Does anyone know of any software that will run on FreeBSD that would >> allow you to keep two servers in sync? All writes to /dir1 on >> server1 would go to /dir1 on server2, and all writes to /dir2 on >> server2 would go to /dir2 on server1? >> >> I've thought about rsync, but am trying to get it as close to real >> time as I can, and on large file systems, rsync would just get too >> far behind, too quickly ... >> >> I've started to look at Coda6, but so far what I'm reading through >> the docs makes it sound like it may not be suitable ... >> >> What I'm looking for is a hot failover solution using FreeBSD ... if >> server1 goes down, server2 can start up and continue working ... when >> server1 comes back up again, changes to server2 could be re-sync'd >> back to server1, and server1 could once more resume its duties ... > > How about a shared SCSI drive, filesystems only mounted on the master. > When the master fails, the slave fscks the filesystems, mounts them, > and becomes the master. Tried and true. You could even use background > fsck and get immediate failover. need to do this above the hardware layer ... am looking at 50% of services running on each of 2 servers, with failover to 100% running on one of the servers if the other goes down ... reading through coda's docs, I think I can do it using that, just curious if there is a simpler setup that could be used ... > You could even do it without shared storage if you use geom_gate and > geom_{mirror,vinum,ccd} to keep two identical disks on each machine in > sync. When the master crashes and comes back up as a slave, the mirror > code will update its disks. what is geom_gate? checked 'man geom_gate' on my 5.x machine, and nothing shows up ... ---- Marc G. Fournier Hub.Org Networking Services (http://www.hub.org) Email: scrappy@hub.org Yahoo!: yscrappy ICQ: 7615664