Alan,
This gives me an idea I have not pursued yet (in fact I am not even
sure where to start :-). Since I can have multiple addresses on a single
machine, would it be possible to tell exim to route outbound messages via
alternate network interfaces based on a condition (such as sender <>)? I
have a separate IP address block for development machines in a secondary
lab. I could static route one of the IP addresses from the lab to my primary
mail server and have it become my sacrificial target.
Tim
-----Original Message-----
From: exim-users-bounces@??? [
mailto:exim-users-bounces@exim.org] On
Behalf Of Kjetil Torgrim Homme
Sent: Wednesday, December 28, 2005 5:03 PM
To: Alan J. Flavell
Cc: Exim users list
Subject: Re: [exim] Return reciept on forward
On Wed, 2005-12-28 at 13:17 +0000, Alan J. Flavell wrote:
> I've just been re-reading http://www.spambag.org/backscatter.html
>
> It appears that this chap takes the view that there can be no
> exceptions; but he offers no viable way of dealing with forwarded
> addresses nor with vacation responses. While I have a great deal of
> sympathy with the rest of what he says, I'm at a loss to know how to
> deal with this aspect.
>
> If he contrives to produce a probe which, as a result of forwarding or
> vacation response at the probed MTA, results in a bounce being
> delivered to his spamtrap, then he'll blacklist the site in question.
> There's definitely a (small) risk that we could do that, if we ever
> came to his attention (which we, fortunately, haven't).
we are using a sacrificial IP address. outbound messages with SA score
3+ (forwarded spam) or sender <> (bounces and vacation messages) are
sent from a different IP address than the main bulk of our traffic. we
use a separate Exim configuration and queue to handle this. even if
Spamcop or others lists this address from time to time, the potential
for harm is quite small.
(we used to use Spamcop to block e-mail outright, but occasionally
they're too aggressive, so we add 3 SpamAssassin points instead now.)
--
Kjetil T.
--
## List details at
http://www.exim.org/mailman/listinfo/exim-users
## Exim details at
http://www.exim.org/
## Please use the Wiki with this list -
http://www.exim.org/eximwiki/
