internal mail server + Postfix (as relay) + ASSP = problem

[iLinkTech]

Hi,
Moving my SMTP proxy over to Postfix as part of platform change (W2K to Linux). My old setup was a W2K IIS5/SMTP server with the open-source Anti-Spam SMTP Proxy (ASSP -

http://assp.sf.net)

application providing anti-spam, whitelisting, and basic anti-virus protection for the gateway. Overall, it worked pretty well but the box was very old and I need the Windows license elsewhere.

Very new to Postfix - want to use it in the following configuration:


Outgoing:
client-->internal mail server-->ASSP*-->Postfix*-->Firewall-->Internet

Incoming:
Internet-->Firewall-->ASSP*-->Postfix*-->Internal mail server-->client.

*ASSP and Postfix are on the same Linux box.

This configuration is identical to what I am using on the existing W2K setup so it should work. According to the ASSP docs, I need to change the line in the postfix master.cf file -

smtp inet ... smtpd

- to -

10025 inet ... smtpd

- so that the internal mail server will communicate with ASSP first (whitelist updating, etc) over port 25. ASSP will then hand off the message via port 10025 to Postfix for delivery.

I have not been able to make this work via Postfix. My internal mail server reports a connection failure in the logs. If I leave the master.cf file alone (default settings), Postfix routes the outgoing mail to the remote mail domain without any delay but it completely bypasses ASSP.

Again, this is how it works w/ the W2K setup - any ideas, suggestions, etc? I've already posted to the ASSP forum but I haven't heard anything yet so I figured that I'd try here as well.

Thanks...

 

[lgarner]

If your internal server is reporting the error, I'd first look at ASSP and see if it's listening on port 25, and responding correctly. Try telnetting to it and sending a message that way.

Check that each piece works individually before putting it together.
1. Postfix- sounds like it works fine on port 25, try it by itself on port 10025
2. ASSP- is it running? If it is and Postfix isn't, try connecting to the server at port 25 and see what ASSP says.

 

[iLinkTech]

Thanks for the suggestion - it turned out that SendMail was still running and hogging port 25, causing ASSP to not be able to listen on that port, even though it did start and would show the admin page.