From owner-freebsd-isp Wed Jul 25 8: 1:12 2001 Delivered-To: freebsd-isp@freebsd.org Received: from mail.online.ie (mail.online.ie [213.159.130.68]) by hub.freebsd.org (Postfix) with ESMTP id 5682037B78E for ; Wed, 25 Jul 2001 07:59:49 -0700 (PDT) (envelope-from bofh@online.ie) Received: from web2.www.online.ie (eth3.web2.www.online.ie [10.10.3.33]); by mail.online.ie with ESMTP id C163C701F; Wed, 25 Jul 2001 15:38:16 +0100 (IST) Received: (from nobody@localhost) by web2.www.online.ie with id PAA11300 Wed, 25 Jul 2001 15:38:16 +0100 To: Fabrizio Ravazzini Subject: Re: FreeBSD Mail Toaster CLUSTER Message-ID: <996071896.3b5ed9d8b73cd@mail.online.ie> Date: Wed, 25 Jul 2001 15:38:16 +0100 (IST) From: Sascha Lucky Luck Cc: freebsd-isp@freebsd.org References: <20010725112323.20541.qmail@web20102.mail.yahoo.com> In-Reply-To: <20010725112323.20541.qmail@web20102.mail.yahoo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit User-Agent: online.ie WebMail program X-Originating-IP: 159.134.245.203 Sender: owner-freebsd-isp@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org Quoting Fabrizio Ravazzini : > Is it possible with FreeBSD to make a "cluster" of two > machines (ix86) that when one goes down for some fault > the other takes care of the service so that Mail is > still available? Fabrizio, set up 2 mail servers and CNAME to both servers in DNS. The 2 servers must access a file system (on a 3rd machine or a shared RAID system, or a Netapp filer) where the mails are stored. Be sure to use qmail with Maildir, otherwise you'll have file locking issues. DNS will assign a connection to to one or the other server using 'round robin'. If one server is down, an incoming connection will have a 50% chance of failure (the more servers, the more likely a successful connection becomes) but on retry it should connect. This setup has been successfully used with approx 100,000 users and 4 mail servers. Alternatively you can use a load balancer instead of DNS. It will notice a server down and reroute connections to the survivor. Good luck, s. ---------------------------------------------------- Get your free email account at http://www.online.ie/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-isp" in the body of the message