[Mimedefang] RBL and DNS lookups

[Kevin A. McGrail]

>> Admittedly, I am biased as a supporter of both SpamAssassin and RBLs. 
>> But I
>> have to say that SA's strength lies in the fact that it is a scoring
>> framework that allows many other tests to be put into the same pool.
>
> Why are you a non supporter of SpamAssassin?

Sorry, my statement must have been unclear.  I heavily DO support 
SpamAssassin and RBLs so if you are looking for a fair and unbiased 
assessment, I might not be the best candidate.

> Constant DNS lookups inject high amounts of latency and system overhead ?

It's relative.  Yes, it takes a few seconds to deliver the emails.  I 
consider this highly acceptable latency.  Yes, there is system overhead in 
performing RBL checks.  I consider them necessary to perform the most 
accurate anti-SPAM tests I can.  So for me, it's a necessary evil.  I do run 
caching nameservers for all of the RBL checking and, in some cases, I run 
local mirrors of the entire RBL.

Regards,
KAM