[Pkg-exim4-users] Reverse DNS lookups

[Bill Horne]

Thanks for reading this: it's a noob question, but I didn't find an 
answer in the FAQ.

I have an Exim4 server running Spamassassin, which I'm using to screen 
spam from an legacy MS Exchange server that my customer isn't willing to 
get rid of.

Since putting exim/spamassassin online, they're very pleased with the 
reduced spam, but they're reluctant to tell some of their senders to fix 
their DNS records. So, I'm looking for a workaround.

I currently have CHECK_RCPT_REVERS_DNS enabled, and one of the senders 
is failing this test. I placed the sender domain into 
CONFDIR/local_host_whitelist, but I'm wondering if there's a more 
universal method of solving the issue.

Here's the problem:

1. Sender is not in a dynamic address pool, but doesn't have a PTR 
record assigned.
2. Sender has an "A" record from a secondary DNS service, which points 
to the address in question.
3. I'd like to accept emails which have an "A" record that points to the 
IP address the email is sent from.

Please tell me if this is a good idea, and how to do it if so. All 
suggestions welcome.

Bill

-- 
E. William Horne
William Warren Consulting
Computer and Network Installation & Service
http://www.billhorne.com/
Voice:	781 784-7287
Fax:	781 784-0951