Idea ID: 2780413

Support for SMTP Submission Port (IP Port 587)

Status : Delivered
over 3 years ago
Would like the SMG service to add support for the SMTP Submission Port (IP Port 587) so it can service our small business customers (and customers running a GroupWise test lab in their home office) that have standard Internet service where IP Port 25 is blocked.

This will allow the SMG customer to have their on-site SMTP gateway connect to the SMG service on IP Port 587. Then the SMG service then connects to the target recipients Internet domain SMTP gateway on the regular IP Port 25.

Many other SMTP AV/SPAM cloud providers support this IP Port 587 as an alternative for their customer that has an ISP blocking IP Port 25.


The reverse direction is also being asked for.

Allow the SMG customer to have the SMG service connect to their on-site SMTP gateway(s) using an IP Port other than 25 (i.e. 2525, 587, etc).


  • We have also needed this for some time (i.e. GWAVA). 

    Rather than running another instance of SMG/GWAVA/etc I simply set up port forwarding on our router/firewall to send all port 587 traffic to Port 25.  I think this is a much lighter and easier to manage configuration.

    Our external DNS MX record obviously points to our router/firewall.  However, we also have our internal DNS MX record pointing to the router's external address so all submissions from mobile devices INSIDE our network can continue to get the same port translation benefit without requiring reconfiguration every time they "cross the boundary".  (Smart Phones, Laptops, etc)

  • This can be achieved already. Adding :587 to the bind address in the SMTP interface will change the port it listens for traffic on. In addition, multiple SMTP interfaces can be configured on different ports to accommodate any combination of bind addresses and port numbers.