On Tue, 4 Jan 2005, Richard Clayton wrote:
> I think the problem may be (I have no traces of actual events, sorry,
> just the log evidence I already posted) that there's quite a lot of
> email to these destinations -- and hence Exim is re-trying addresses
> that are already past their retry limits; and these don't count towards
> the total. This was apparently a change made in 4.11
Yes, that was done so that it would try all IP addresses before timing
out a message. Sigh.
> what I'm suggesting is that sites that are not being silly may have a
> fair number of "possible IP addresses" but not hundreds.
A very good point.
> yes indeed -- so what I'm suggesting is that an anti-DOS mechanism is
> needed.
Oh, I entirely agree. It is a pain, but I guess we have to adopt
something.
> I can see that some cleverness is needed to deal with sites that
> genuinely need a dozen fallback MXs -- though I note that people like
> AOL who used to work that way no longer do so -- so I wonder how many
> there are of these on today's Internet ?
If the default were set at, say 50, I think we can argue that any
"reasonable" set-up should not be affected by it.
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.
Get the Exim 4 book: http://www.uit.co.uk/exim-book
