Hello,
I am using XEAMS email filtering appliance, and would like to change the SME server listening port 25 to some other port so that spammers will be less inclined to send directly to my SME server. The idea is to set the port to another value, and then set that port in XEAMS so that anyone sending emails that tries to connect to the SME directly will not be able to without knowing the port that I set, but the XEAMS will be able to forward the legit emails using the new port. The XEAMS server has its own MX record with top priority, and the SME server is second in line. Most emails are coming in through the XEAMS server as they should, but it seems that some spammers have cached the IP of my SME server and are still hitting it directly. I tried to use "config setprop smtpd TCPPort "someport" and then /etc/init.d/qpsmtpd restart along with signal-event email-update but it seems that the new port that I set may be getting blocked by the iptables firewall. Which commands would I use to properly reset the port and add the new rule(s) so that the new port is able to be open to the outside?
Thank you and I hope this all makes sense.