Dennis // [EMAIL PROTECTED] wrote:
Hi all.
I manage a few postfix spamfilter gateways for my company.
They are doing a really god job of scanning mails and delivering them to
customers mailservers.
The way we implement this is using a catch-all address to accept all
mail for customers domains, then scan the mail and try to deliver it to
the customers mailserver.
This is of course a less than ideal solution, as i´m currently accepting
a lot of mails for remote-addresses that are non-existing. Which means a
few 100k mails scanned every day just to have the remote server bounce
it as the recipient does not exist.
Right. If you send enough backscatter, you'll get blacklisted.
I then thought of using the "reject_unverified_recipient" parameter,
thus letting the spamscanners probe the remote mailserver to see if the
recipient is valid or the mail would bounce.
A fine solution if you are unable to get an actual list from
the remote mailservers.
My questions are:
As the spamscanners are the best or primary MX´s
for the customers domains, would postfix then just probe itself, and
always get a positive answer due to my catch-all entry ?
Or would postfix actually look at the transport map, and realize that it
has to probe the customers server. ?
Postfix uses its normal routing methods with verification
probes. If "normal" mail goes to the right place,
verification probes will use the same channel.
And how would one go about controlling the destination of the
probe-messages ?
You probably don't need this, but here are the docs for probe
routing:
http://www.postfix.org/ADDRESS_VERIFICATION_README.html#probe_routing
--
Noel Jones
