Ray,

SpamFilter is designed to handle your *incoming* email only. Your local users (and admins...) should still have in their "outgoing SMTP server" settings in their email clients the address of your Imail SMTP server, not SpamFilter. Your Imail then delivers the outgoing emails to the outside, bypassing SpamFilter.

Roberto Franceschetti
LogSat Software

SpamFilter is designed to process incoming email only by acting as a proxy to your mail server. The main thing to remember is that outgoing email from inside your network to the internet should never pass thru SpamFilter. There are several ways to configure your network to enable this to happen.

Assume your SMTP server is mail.aumteam.com. You don't want to change that, so your clients will always point their outgoing mail to that.

If your mail server is behind a firewall, and the firewall allows is, all you need to do is to configure the firewall so that incoming connections on port 25 are sent to the IP SpamFilter is listening on (different than mail.aumteam.com), rather than sending them to your SMTP server. Then configure SpamFilter to forward email to your SMTP server.

If the above is not possible, you can change the MX record in your DNS to point to the name/IP SpamFilter is configured for. SpamFilter then forwards to your SMTP server. The IP/name of your SMTP server does not change.

There are a few more postings on this subject on this, along with a sample DNS configuration for the second option at http://www.logsat.com/spamfilter/details.asp

Roberto Franceschetti
LogSart Software

Ray,

Everything makes sense and looks fine, but there is one "but". If your customers are outside of your internal network, and thus are coming in from the internet, if they are accessing their outgoing smtp server (IMail) on port 25,  your router will reroute them to port 84, which is SpamFilter, and you are back to having the original issue...

If you only have a single IP address available, the only option I can currently think of is to change your client's outgoing mail server configuration.

Possible examples:

Ex.1: The router does not do port translations. SpamFilter listens on port 25, IMail on 84, SpamFilter forwards to 84, your clients point to port 84.

Ex.2: The router forwards port 25 to 84. The router also forwards port 26 to 25. SpamFilter listens on port 84. IMail listens on port 25. Incoming mail on port 25 is then sent to SpamFilter on port 84. SpamFilter then forwards to IMAil on port 25. Your customers configure their outgoing smtp for port 26. When they reach your router they'll be translated and sent to port 25 on your IMail.

Roberto F.
LogSat Software

Ray,

We assumed that you only had access to one single IP from your provider, and the suggestions we ghave before were based on that. Yes, of course if you have multiple internet IPs available (not internal LAN IP, they have to be internet IPs) things are much simpler.

It's extremely easy to bind multiple IPs to a single NIC card in one computer. We've prepared some screenshots on how to do so, click here to view them.

We see that your MX record for comcast.net points to mx00.comcast.net (24.153.64.1). If that is what your clients use as their outgoing smtp server, and you do not want to change your clients configs (which is what we recommend), you will need to have SpamFilter listen on a different IP, let's say 24.153.64.2 for example. The only thing you will have to change then is the MX record so that it points to SpamFilter's IP, 24.153.64.2.

By doing that incoming email will go where the MX record direct it, SpamFilter in this case. SpamFilter will then forward it to your IMail server on 24.153.64.1. Your clients will not change a thing, and still point to your IMail at 24.153.64.1.

Hope this helps.

Roberto Franceschetti
LogSat Software

Yes, you can use another NIC, but you don't have to. You can add many additional IPs to the existing NIC card without the need for an additional one. I believe we have about 500 IPs bound to a single NIC card on one of our webservers.

Roberto F.
LogSat Software

Solution requiring changing the mail server and mail client ports.

25 --> spamfilter --> 26 --> mailserver

Using this method, spamfilter accepts incoming on 25 and routes it out to 26.  The mailserver gets it from 26 and stores it.  The email clients send using 26.  I did not have to change the email outgoing port back to 25.  Thanks ISP : )

--- OR ---

solution where you don't have to change the mailserver or client workstation ports.

25 --> WAN domain mapped --> 26 --> spamfilter --> LAN Domain:25 --> mailserver.

The mailserver is on the LAN side.

Using this example, I would think that the client workstations, hopefully already using LAN ip's, will go directly to the mailserver only to ask for email on port 25.  Port 25 on the WAN side will convert only WAN requests, not LAN request.  I use winroute pro to do this.

All based on everything sitting on one computer.