[Mimedefang] OT: sendmail limit connections

[Sven Willenberger]

On Wed, 2005-02-23 at 11:15 -0600, -ray wrote:
> I have max daemon children set to 250.  Occasionally one machine will open 
> 250 connections, probably spamming, so sendmail stops new connections.
> 
> Is there a sendmail way to limit # of connections by ip address?
> 
> ray

Another feature, in addition to rate throttling and connection
throttling in 8.13.x , is the greet_pause feature which delays the
initial 220 greeting upon connection by up to x milliseconds. Any
connected server trying to issue mail commands prior to the 220 greeting
will get met with 550 failures; this is useful for a lot of zombies, etc
that just blast out spam/virii without any adherence to protocol.

Sven