Re: [Exim] Greylisting + multiple MX hosts -> multiple attem…

On Tue, 23 Mar 2004, Alun wrote:

> "Alan J. Flavell" (a.flavell@???) said, in message
> > (hello, Aber, this means you ;-)
>
> Hello!

Hi ;-)

> > The answer was that their MX entry pointed to three IP addresses, and
> > as the retry time came around, we were making three retries in rapid
> > succession to them. As Chris E said to me, this is in fact correct
> > behaviour in response to a 4xx status; it just so happens that - in
> > the case of greylisting - the repeat attempts are a rather pointless
> > activity.
>
> Indeed.

[...implementation details snipped...]

Interesting, of course; but the point that I was making was a
different one.

I've since been taking a look at the retry rules definitions in the
exim documentation (chap 32 as well as section 43.2 seem to be
relevant), but there doesn't seem to be a way of defining a retry rule
that will be used in response to even _any_ 4xx status during the
course of the transaction - let alone one that would only be used when
the peer MTA got told it was being greylisted.

Maybe I'm making this overly complicated (it's happened before ;-) by
trying to avoid the MTA causing pointless extra network traffic in
such a situation. I suppose I should just let it take its natural
course. But for a 60min greylisting, for example, it means (at our
initial 15min retry interval) about 4 rounds of retries, times the
number of IP addresses in the MX lookups, i.e in this case a dozen
retry transactions.

Ho hum.