From owner-freebsd-hackers@FreeBSD.ORG Tue Oct 11 09:10:50 2011 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 4141E106564A for ; Tue, 11 Oct 2011 09:10:50 +0000 (UTC) (envelope-from kraduk@gmail.com) Received: from mail-yw0-f54.google.com (mail-yw0-f54.google.com [209.85.213.54]) by mx1.freebsd.org (Postfix) with ESMTP id F2B4F8FC0C for ; Tue, 11 Oct 2011 09:10:49 +0000 (UTC) Received: by ywp17 with SMTP id 17so7926462ywp.13 for ; Tue, 11 Oct 2011 02:10:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=1kXOCkQ66PHCvxYOKwOzXZC15S3wbEMEXLKfXJQNogs=; b=JTYz8dtCC9MvUybM23LTpDftq1zYzs4lTYOrLGzvc7lRv+BT3BGqD5yA8wqdFZI76i bKLdAum9xlKKwL+BzLafGhrqNVDtXHKYZaUC/8/z7x4OYIiplJsmemm63P9oNWuK8aFZ BtyWeM+JpinzVT2LReEg5eUkWhlU26gdR5zz8= MIME-Version: 1.0 Received: by 10.236.129.228 with SMTP id h64mr28939737yhi.101.1318322440374; Tue, 11 Oct 2011 01:40:40 -0700 (PDT) Received: by 10.236.109.133 with HTTP; Tue, 11 Oct 2011 01:40:40 -0700 (PDT) In-Reply-To: <4E93F58D.6040004@my.gd> References: <415606854-1318275087-cardhu_decombobulator_blackberry.rim.net-469635454-@b3.c1.bise3.blackberry> <4E93F58D.6040004@my.gd> Date: Tue, 11 Oct 2011 09:40:40 +0100 Message-ID: From: krad To: Damien Fleuriot X-Mailman-Approved-At: Tue, 11 Oct 2011 16:43:00 +0000 Content-Type: text/plain; charset=ISO-8859-2 Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-hackers@freebsd.org, elman_syah@yahoo.com Subject: Re: Clustering server in freebsd X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 11 Oct 2011 09:10:50 -0000 On 11 October 2011 08:51, Damien Fleuriot wrote: > > > On 10/10/11 9:31 PM, elman wrote: > > Dear all > > > > I have plan to cluster server with freebsd 8.2 for mailserver. But I'm > confusing with the software for clustering. Do you have a reference for m= e, > or do you have blog and I can see your blog for reference to create > clustering with freebsd. > > > > Thanks hacker > > Best regards. > > Mr. L > > Powered by Telkomsel BlackBerry=AE > > > > Your question is very vague. > > - what goal do you want to achieve ? > - do you want a redundant mail system in case one of your servers goes > down ? > - do you want a load balanced system to distribute the load (incurring a > degraded service if a server goes down) ? > - what do you mean by "mailserver", is that for outbound and inbound > email (SMTP), for users to grab their email (POP,IMAP), or both ? > > > > Basically you're giving us a *means* (clustered servers) to an *end* > that we do not know/understand. > > You've thus had 2 responses so far which might or might not have been > helpful because nobody knows what you're trying to do ;) > > If you want meaningful answers, you'll have to be much more specific. > _______________________________________________ > freebsd-hackers@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-hackers > To unsubscribe, send any mail to "freebsd-hackers-unsubscribe@freebsd.org= " > I have built a few resilient mail platform over the past few years, in highly available, high volume isp environments. In my experience its a bit more complicated than having a cluster. What you need is a resilient environment. How much resilience you build in is really down to the busines= s requirements verses the cost. Some parts of the mail system would make sens= e to be clustered, whilst others do not. SMTP inbound doesnt need clustering resilience takes care of itself by specifying multiple mx records of the same priority, although a load balancer does have merit here, but isnt required. Same goes with any spam filtering you do on the mail. Most mta allow you to specify multiple av/spa= m scanners, and round robin their use. Alternatively you can just run them on localally (not ideal for scalabillity). SMTP inbound (for pc email clients) you can do dns load balancing but a proper load balancer is better here. Pop3, imap, load balanced. You would probably want to make the connections sticky on relation to the source ip though. You would then get the benefits of caching etc, by all of the connections from the same user hitting the same head end. What out from large numbers of users comming from a nated ip though if you do this. Webmail head ends - load balanced. Definately need sticky connections here as session ids get screwed up to easily otherwise. Webamail back end - Clustered. Most webmail solutions out there require a d= b backend (sqwebmail doesnt from what i remember). This has a lot of writes, therefore needs to be clustered. Backend authenticaion (webmail/pop3/imap) - depends. If its ldap you can probably just get away with a master server and multiple slave ldap servers replicating off this. If its a db (mysql) you could do a similar setup with reading from some slave servers, or as you most probably have a cluster for the webmail backend you could use that. Shared storage: Definitely need to be clustered. Could be a resilient netap= p type thing, sun cluster, red hat cluster, or possibly some kind of hast solution. Personally I would use a solution based on wafle or zfs. Which yo= u go for really depends on your budget. Database clusters: 3 main options here really. 1. Mysql cluster - could run on freebsd (offical mysql cluster commercial) you can do a diy cluster though there are a few guides out there. 2. redhat cluster - supports most dbs 3. sun cluster - there are other cluster software available (veritas) but they get very costly and are probably overkill. WHich ever db solution you go for i'd recommend you use one that is underpinned with zfs, as it makes backing up dbs very quick and easy, as well as the data integrity advantages it provides Load balancers - there are many commercial options here, although you might want to look at relayd is you want opensource. Its probably best to run it on openbsd though as you will get the full range of features then. As you can see its quite a complicated affair to what seems a simple question. But it basically boils down to at present there is no proper clustering solution for freebsd, however there are plenty of roles that freebsd does an outstanding and cost efficient job in a resilient environment