address harvesters

always hammer at my system, but i have ended up blacklisting them by ip
addresses... I never had any problems with DCC falling over but mimedefang
will fall over on my machine, and if that doesnt, well I have seen Vexira
(milter mail armor product) fall over once or twice... I end up having to
restart things about every 7 days or so because of this. (I have had 20
connections open to a single machine trying to harvest, with three
machines doing this (60 spam harvest connections) and no problem....
but i have it running on a 2xP3-1.4G/1G ram/3x36G on a megaraid... a
hardened rh7.2 install (minimal packages)

One thing that i did which helped was to keep the "invalid addresses
before delaying" sendmail parameter down around 10, and the max
connections/second down below 5. (I also made sure the submit program runs
5 more copies than the main sendmail... this helps lots)

-j.