From owner-freebsd-net  Mon Mar 22  1:21: 3 1999
Delivered-To: freebsd-net@freebsd.org
Received: from rose.niw.com.au (app3022-2.gw.connect.com.au [203.63.119.4])
	by hub.freebsd.org (Postfix) with ESMTP id 5BA3B15218
	for <freebsd-net@freebsd.org>; Mon, 22 Mar 1999 01:20:47 -0800 (PST)
	(envelope-from ian@apdata.com.au)
Received: from apdata.com.au (localhost [127.0.0.1])
	by rose.niw.com.au (Postfix) with ESMTP id 7D5C6A3203
	for <freebsd-net@freebsd.org>; Mon, 22 Mar 1999 19:50:21 +1030 (CST)
Message-ID: <36F60B55.1EEFB167@apdata.com.au>
Date: Mon, 22 Mar 1999 19:50:21 +1030
From: Ian West <ian@apdata.com.au>
Organization: Applied Data Control
X-Mailer: Mozilla 4.5 [en] (X11; I; FreeBSD 4.0-CURRENT i386)
X-Accept-Language: en
MIME-Version: 1.0
To: freebsd-net@freebsd.org
Subject: Re: clustering/load balancing
References: <199903220807.LAA06347@main.piter.net>
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Sender: owner-freebsd-net@FreeBSD.ORG
Precedence: bulk
X-Loop: FreeBSD.org

"Cyril A. Vechera" wrote:
> 
> > From owner-freebsd-net@FreeBSD.ORG Mon Mar 22 07:28:07 1999
> > To: Julian Elischer <julian@whistle.com>
> > Cc: Christopher Sedore <cmsedore@maxwell.syr.edu>,
> >         "'freebsd-net@freebsd.org'" <freebsd-net@FreeBSD.ORG>
> > From: "Gary Palmer" <gpalmer@FreeBSD.ORG>
> > Subject: Re: clustering/load balancing
> > Date: Sun, 21 Mar 1999 23:27:43 -0500
> >
> > Julian Elischer wrote in message ID
> > <36F1BA88.2F1CF0FB@whistle.com>:
> > >                                  +-------[Machine B]
> > >                                  |
> > > [internet]-----[ Machine A ]-----+-------[Machine C]
> > >                                  |
> > >                                  +-------[Machine D]
> >
> >                    ^^^^^^^^^
> >
> > Single Point Of Failure
> 
> in the original scheme 'single point of failure' is still present.
> 
>                                   +-------[Machine B]
>                                   |
>  [internet]-----[ any router ]----+-------[Machine C]
>                                   |
>                                   +-------[Machine D]
>                    ^^^^^^^^^
> 
> or maybe you can see other way to connect 'internet' to Machine [B-C]?
> 
> what is the differense between 'any router' failures and 'balance
> dispatcher' failures?
> 
> Sincerely your,
>         Cyril A. Vechera
> 
> email:cyril@piter.net          ---------              http://sply.piter.net
> 
> To Unsubscribe: send mail to majordomo@FreeBSD.org
> with "unsubscribe freebsd-net" in the body of the message

I have a very similar problem, I am not so much interested in load
balancing as fault tolerance. I have been looking at implementing vrrp,
which being standard (almost...) would allow a bsd machine to provide
redundancy for a router, or allow two bsd machines to provide redundancy
for each other. It does not provide load balancing that I can see, but
possibly with judicious use of forwarding this could be achieved. The
url for the latest draft I am aware of is below

http://www.ietf.org/internet-drafts/draft-ietf-vrrp-spec-v2-01.txt

I have not spent a lot of tie on it yet, but as far as I can tell, it
should not require much other than writing a daemon which would
implement the polling/advertising, load the multicast bits into relevant
interface(s), and put the actual 'virtual' router address onto a
loopback interface. (The loopback seems like the easiest way to make the
ip address respond to traffic, but not to arp requests, without changing
kernel stuff.) 

These are my thought to date, and hopefully I will be able to start
writing something in a couple of weeks. It is more than possible that I
have overlooked something enormous which will be a real show stopper,
but this is a function I need, and it may suit quite a few applications.

Any comments ?

Regards,
Ian West


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-net" in the body of the message