[prev in list] [next in list] [prev in thread] [next in thread] 

List:       exim-users
Subject:    Re: [exim] Sender rate limiting based on recipient address?
From:       David Woodhouse <dwmw2 () infradead ! org>
Date:       2015-11-09 11:00:33
Message-ID: 1447066833.81031.40.camel () infradead ! org
[Download RAW message or body]

[Attachment #2 (multipart/signed)]


On Tue, 2015-10-20 at 07:51 +0000, Osborne, Paul
(paul.osborne@canterbury.ac.uk) wrote:
> 
> So when google generates the MDF it goes to mxout (as part of the
> SMTP transaction) - which then sends it round to mxin and so back to
> the beginning of the pipeline.   It is all made worse by our addresses
> in O365 actually being something like:   paul27@mysite.onmicrosoft.com
>   - so by the time the address has been rewritten any sense of the
> original inbound mail and any MDF due to the forwarding issue is a
> right pain to correlate.

I must be missing something here. The important part of a bounce
messages is not the destination, but the *sender*. Which must always be
empty — MAIL FROM:<>.

Such messages can never trigger a mail loop, because they must *never*
trigger any kind of autoreply.

So even if your user were to send *himself* a message, it should
generate a bounce. That bounce is undeliverable too, but that *doesn't*
in turn produce another one.

This is the very basic principle of how bounces work; if you are
violating this somehow, then you need to fix *that*, not play with
rate-limiting.

-- 
dwmw2


["smime.p7s" (application/x-pkcs7-signature)]
[Attachment #6 (text/plain)]

-- 
## List details at https://lists.exim.org/mailman/listinfo/exim-users
## Exim details at http://www.exim.org/
## Please use the Wiki with this list - http://wiki.exim.org/

[prev in list] [next in list] [prev in thread] [next in thread]