On Wed, 2005-10-26 at 16:43, Benjamin Smith wrote:
> On Tuesday 25 October 2005 18:41, Les Mikesell wrote:
> > Does your 'outside' box have access to the user names or
> > does it blindly relay everything to the inside box?
>
> Blind as bats. Why?
Look at your logs to see how much you are accepting on the
outside box with corresponding CPU work only to have the inside
box reject the recipient and force a bounce. Aside from having
a lot of ex-users, I get hit with dictionary type attacks on
several domain names (thousands of users that have never existed).
If you have the same issues, you might fix your efficiency problem
by rejecting unknown recipients early in the conversation. That
not eliminates the spam/virus scan, but someone else has to construct
the bounce.
If you can't directly access the valid user/alias names or convert
them to virtual users on the outside box, MimeDefang has a method
to check recipients over smtp against the real destination host
as part of the milter operation.
--
Les Mikesell
lesmikesell at gmail.com