Author: Lee Maguire Date: To: exim-users Subject: Re: [Exim] Bounce messages against me
[2002-02-18] Dave C. wrote: > > domain. ( for example 0123fee54323@??? ) .
[snip] > Set receiver_verify, to at least prevent your server from accepting
> messages for (random characters)@dicea.unifi.it (This is presuming you
> dont accept "*"@???,
I've been in this situation, and the problem with setting
receiver_verify is that there appear to be plenty of mail setups that
don't seem to recognise a "550" response when delivering DSNs, and will
just queue and retry. There appear to be some that will immediately
retry delivery.
This was maxing out the connections on the affected server, and then
caused backup MXs to max out. (This was a pump-n-dump spam on a
massive scale.)
In the end I needed to write a system filter to match the DSNs and
:blackhole:'d them. (In fact I ended up copying them to a specific
mailbox to extract data for RBL submissions.)
The bounces kept coming for over a week, despite the fact that one
of the injection points was a dialup range operated by one of our
upstreams.
> which you shouldn't be doing.
(unless your site has a "all mis-addressed mail to postmaster" policy.)
