Up until now, I've allways denied hosts that have no valid rDNS and
occassionally had to white list one or two along the way because they were
unable to fix their problem.
This is with my own server, and a number of medium sized non-profits.
Recently, I activated a large company mail server and am finding there are
a lot of screwed up mail servers out there.. to the point that I am having
to whitelist a number of boxes just to get mail in.
So I am rethinking this a bit....
Right now, I am thinking of allowing hosts without valid rDNS in, but
marking them so that SpamAssassin can mark them a potential spam and then
starting the reverse, a black list of known bad sites that are blocked
outright.
This looks like a time consuming project either way, I'm curious how
others are dealing with this.
This particular site has about 4300 users with so far a light mail load
(Holidays)...
I am amazed at how many mid-sized companies that have misconfigured mail
systems.
--
Kevin W. Reed - TNET Services, Inc.
Unoffical Exim MTA Info Forums -
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