Port Forwarding for SMTP

[tiggi]

Due to restrictions on one of our clients ISP they have to connect to SMTP via port 26.
We have AMS installed on server 2008 and it works fine. We configured port forwarding in NAT from port 26 to port 25.
When I try to telnet to port 26 I get an answer from AMS but when I try to test connection in Outlook it times out.
Has anyone had similar situation?
Thanks

[Code Crafters]

If telnet works ok with a quick response time, make sure that your outlook really does point to the correct mail server and port. You may need to recreate the account in outlook to get it to work. If there is a delay, you should reduce the SPAM Transaction Delays. If not, you can check the SMTP logs to see what errors and activity is happening for the outlook's IP connecting to your mail server (if it is doing of course).

[tiggi]

Thanks for your reply...

All info in outlooks is correct. I created an account using port 25 and it works just fine but when I switch it to port 26 it times out.
I am lost....

[Code Crafters]

I'm guessing your outlook is accessing from inside your network which may mean that it accesses the mail server directly rather than going through your router which would explain the port difference. If you access via your mail server domain then it may go through your router but you can of course change the AMS port to 26 instead of 25 as well.

[tiggi]

Mail server is not inside the local network so connecting to it via IP or domain gives me same result.

[Code Crafters]

Maybe your router isn't properly configured to pass port 26 then. Remember it must be setup from port 26 to the mail server static LAN IP on port 25 internally. Also, remove the mapping for port 25 if needed. However, you must understand that normal mail delivery from other mail servers to yours will require that port 25 can accept mail. Therefore, if you cannot get port 25 to work on your network, you may have to pay for a simple port forwarding service from a company like www.no-ip.com who can accept mail on port 25 and forward it to another port at another localtion (i.e. port 26 on your network).

[cearnshaw]

On this same topic, is it possible to have AMS accept SMTP on both port 25 and an alternate port? The problem we have is some customers cannot sent port 25 when they are traveling outside our network (due to blocking of port 25 by their local ISP) so we want to let them sent their mail on port 26 whenever they cannot get through on port 25. I haven't found a way to do this with a NAT rule without disrupting my normal port 25 traffic.

Cam

[Code Crafters]

Currently Ability Mail Server 2 can only listen on a single port. However, AMS3 (and Ability FTP Server 2 due out in the next few weeks) will use new IP control and IP binding systems that allow you to control multiple ip/port pairs for a single service.

For now, you can achieve this by either:

a) configuring your router to forward both ports 25 and 26 to 25 internally on the AMS network IP (if your router allows this of course).
b) using a port forwarding service from a provider like http://www.no-ip.com to forward port 26 for your domain (or sub domain) to your mail server Internet IP on port 25.