MonitorWare Knowledge Base

Hello,

Have any Exchange 2003 mail admins out there had any luck blocking spam by somehow blocking all
messages whose sending mail hosts do not resolve correctly to a reverse DNS query?
If so, can this technique be done with the Windows 2000 virtual SMTP server, or are you
using a third party software solution? I was thinking of setting up a second host and
installing the Microsoft SMTP service receive mail from the internet and forward on to our Exchange 2003 server. This bridgehead server would theoretically be doing the reverse DNS blocking. Thanks for your help!

-Matt Corbett

Hi,

not really. For that reason we use a postfix based mail-gateway. It is running very well on a little Debian machine. So Email must pass through our postfix rules, and is then forwarded to our Exchange Server.

I am pretty sure this is not really the solution you expected but it works

best regards,
Andre Lorbach

Thanks for your help and such a quick reply!

-Matt Corbett

I found some tutorials you might want to start with:
http://www200.pair.com/mecham/spam/
http://www.linuxplanet.com/linuxplanet/ ... ls/5561/1/
http://linuxtoday.com/news_story.php3?l ... 6-OS-HL-NT