1. Mailcow

Source: Tony Teaches Tech Mailcow docker configuration

To host your own mail server is not like hosting any other application. Why you might ask ? Well this has to do with spam and lots of it and also internet service providers blocking port 25 on which your mail is running on.

But

well, we will show how to run your own mail server regardless since it is great for learning purposes and you can have as many email addresses as you want. You don't need to pay a monthly subscription for every email address. Imagine you want x email addresses for all of your contributors then that is x times the yearly price to host an email .That can get expensive really quick. 

So the first thing we need to make sure of is that you own a domain name. Yes, sadly enough this is still held by middle man that make millions of dollars each year by just being that. As stated everywhere else we are working on changing this to a more non profit based structure or completely decentralized with technologies like handshake. Next up, is adding DNS records to your domain name that you will use for your email server. The minimum records you should add are the following Type Name Target A example.org Public IP address of your email server A mail.example.org Public IP address of your email server

Public IP address of your email server

Public IP address of your email server