Open Relay Checker before Opening MTA

Neil Symons neil at
Sun Feb 10 00:58:57 EST 2002

I wonder if there is already something like this out there before I write one myself.

When a mail server connect to me, I check my local blacklist to see if server is listed as an open relay, if not, then check my goodlist, if not there then connect straight back at them and do a open relay test.

If all successfull, then accept connection and open real Mail Transport Agent (Mail server) and carry on through the e-mail. And add them to my Goodlist

If it is found to be open relay, then REJECT e-mail and also e-mail postmaster of domain about what happended.
Add site to local blacklist.

Once per day/week/month go through each blacklist and whitelist to check if open relay and adjust accordinly.

Even though this may use up bandwith, it will at least be less than the amount of junk mail received these days.

Does anyone have any suggestions to whether this is a practical thing to do, or simply a stupid thing to do?


-- Neil

> Neil Symons <neil at>                        <
> Goldweb Internet - (02) 62530059 BH  (0500) 528932 AH    <
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