florian wrote:ok, now finally, if you ping "myhost.mydomain.com" - does it go to 127.0.0.1 or your official IP address? If the latter, than actually the message must be flowing through the Scalix system from SWA, no matter what the recipient is.
ping mail.mydomain.com goes to the external, public IP address. mail.mydomain.com is the hostname reported by "hostname" and "hostname -f" . Additionally, ping mydomain.com doesn't resolve to anything (which is correct from my point of view as there is no server there) but could this have an effect on the mail traffic?
florian wrote:SWA --> SMTP --> Port25/hostname --> omsmtpd --> unix.in --> service.router --> unix.out --> SMTP --> Port 25/localhost --> sendmail --> RestOfWorld
The tcpdump idea should capture traffic on the Port25/localhost part of the journey.
So from my answers above, it seems that emails from SWA to the rest of the world behave OK, but if they're forwarded using a rule, then they don't travel this path.
florian wrote:Now, you can capture traffic on the Port25/hostname journey also through tcpdump or by setting up DEBUG_LOG=TRUE at the beginning of the file in smtpd.cfg and restarting the SMTP relay.
Last time I did this I waited 12 hours for a repeat occurrence of this X, and ended up trying to wade through 20 Mb of logfile. Needless to say, everything behaved perfectly during this period.
florian wrote: similarly, you can see how the message progresses through the system by setting an audit level of 9 for internet gateway (with omconfaud/omshowaud)
This is a new approach to me. I'll try it and let you know.