Spamfilter setup on a Windows 2000 Professional workstation, used to
accept mail - rejecting the spam. Then it is supposed to forward the
messages along to qmail running on Fedora Core 2 server.

Problem is some email will be successful when getting forwarded along to
qmail and some will not (for the same domain).

Here are the symptoms as I have identified them so far:

1) Spamfilter accepts the message
2) Attempts to send the message along, and will try to establish a
connection to the remote server for delivery.
3) The qmail server will place an entry in its logfile upon connection:
Jul 1 10:23:02 s1 relaylock: /var/qmail/bin/relaylock: mail from
60.115.247.75:1225
4) The two server will just sit there for a while (1 minute?), eventually
Spamfilter will record an entry that looks like this:
Socket Error #10054 Connection reset by peer. - forwarding to:
116.69.165.64 - message qued - email@email.com

That is it, it never gets any further than that. The qmail server never
makes mention of the connection again in its logfile.

I thought I would then use the debug view tool in spamfilter which
monitors the SMTP data between the two servers. I placed the ip address
to monitor but nothing showed.

Of course, I assume the debug tool is not working. I then changed the ip
to monitor to * and I start seeing server communications (not between the
two servers in question though).

So from debug tool I can conclude that they never establish a connection
good enough to even transfer an smtp command.

I can manually telnet into port 25 from the spamfilter machine to the
qmail server and issue the commands by hand to send a message so I
know port 25 is alive and well.

Anyone got some additional things I should be checking here?

caratking,

The debug monitor in SpamFilter will only monitor incoming connections, not the outgoing ones.

Usually outgoing communications to your SMTP server are pretty straightforward and do not cause problems, so there is very little debugging built in SpamFilter for this. The "Connection reset by peer" error indicates that the peer server (qmail in this case) has disconnected SpamFilter.

If the qmail logs do not have any additional information, I would suggest using an external monitoring tool to watch traffic from the SpamFilter server to your qmail server. If you had a server version of Windows you could have used it's Network Monitor utility. In your case, you could use Ethereal (www.ethereal.com). It runs on both Windows and Linux, and it's very possible your Fedora Core distribution already has it installed.

We had already modified it right after your first post !
It was indeed not clear as it was phrased.