Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 25 Jul 2000 15:17:46 -0500
From:      Dan Nelson <dnelson@emsphone.com>
To:        Shawn Ramsey <shawn@megadeth.org>
Cc:        questions@FreeBSD.ORG
Subject:   Re: packet filter
Message-ID:  <20000725151746.A17756@dan.emsphone.com>
In-Reply-To: <4.3.0.20000725124243.0220e008@mail.cpl.net>; from "Shawn Ramsey" on Tue Jul 25 12:44:22 GMT 2000
References:  <4.3.0.20000725124243.0220e008@mail.cpl.net>

next in thread | previous in thread | raw e-mail | index | archive | help
In the last episode (Jul 25), Shawn Ramsey said:
> Is IPFW or IPFilter capable of random port redirection? Such as a request 
> comes in for port 25, can it randomly redirect this request to another 
> server? (such as multiple mail servers, sort of a load balance)

You can do it two ways:

1. With the "ipfw fwd" command (possibly the ipf "dup-to" comamnd
also): forward packets with a source mask of 0.0.0.0/4 to IP#1,
64.0.0.0/4 to IP#2, 64.0.0.0/4 to IP#3, 64.0.0.0/4 to IP#4.  Limited to
filtering on source addresses, so your load probably won't balance
eavenly, but very fast.

2. Run "natd -redirect_port tcp ip1:smtp,ip2:smtp,ip3:smtp mail:smtp". 
This round-robins incoming connections to "mail" to ip1, ip2, and ip3,
but takes a bit more CPU.  It's got it's own RFC: 2391

-- 
	Dan Nelson
	dnelson@emsphone.com


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




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20000725151746.A17756>