[TriLUG] sendmail vs. postfix - was Re: stupid sendmail question?

[Tanner Lovelace]

Aaron S. Joyner said the following on 6/16/04 4:50 PM:
> Postfix does not have Sendmail's milter 
> interface.  What the Milter interface allows you to do, is reject 
> messages on the fly, as part of the SMTP session, for what ever reason 
> you see fit.  Spam, Viruses, Malformed messages, what ever -- you don't 
> generate NDRs, you just say "No Thanks" and stop talking to the sending 
> host.  Postfix does not have an elegant way to implement this.  You can 
> sit a spam/virus daemon in front of your MTA that's capable of doing it, 
> but that's not an elegant solution.  For most low volume sites this 
> isn't really a problem, but for larger volume sites it can be a real 
> headache as queue sizes grow unmanageable.

Postfix can reject based on regular expressions, which can be fairly
powerful.  It can parse both the header and the body for this and
rejects at SMTP time instead of generating bounces.  Newer versions
of postfix can also delegate policy for receiving e-mail.  This allows
it to implement greylisting which can apparently cut down on the majority of
spam out there.

Cheers,
Tanner