How can I map local mail server to my domain

[zentuser]

I've setup local mail server on Linux Platform,now I'm able to access within LAN, I've purchased domain from GoDaddy, how can I map local mail server in my domain ?

I know that we need to give mail server IP in MX records of the domain but the issue is with my network architecture,once have a look

Static IP Address from ISP---> Net Gear Router--->eth0 of Linux server;from eth1 of Linux server to LAN.

Now we are able to access mail server by using local IP address as

192.168.x.x/webmail or by configuring SMTP details in Thunderbird.

I want to access webmail outside of local network,how can I do this ?

 

[PhilFrisbie]

Assuming your ISP does not block servers, you need to forward the appropriate ports from your router to your mail server, then set up the MX records.

NOTE: You will still need to use the IP address when you are inside your LAN.