Hello… I’m looking to setup mailinabox locally. I have my local nameserver set up on another VM, and it’s running properly. I’ll set the needed records for my mail server there and also import certificates from my cloud server to use it locally. However, I’m confused as how to setup mailinabox itself. In the setup script, it seem to be picking my ISP’s IP address as my public address. Fair enough …but I just don’t know how that’ll affect things.
To run a mail server, you need a static IP provided by your ISP, that has all the ports open to allow mail traffic. You then need to setup your router to forward that traffic to the mail server on your network. MIAB reports what the public facing IP is during setup.
You could, in theory, run MIAB at home over a residential Internet connection but it’d only be able to receive email, not send it. It would mean using DDNS so that your hosted domain could always be found and then use an SMTP service to relay mail out over a secure port as 25 would be blocked.
Frankly, the days of running email at home are long gone. It’s an exercise in futility.