Mail system for your own domain
You have your own domain name and your very own vps/dedicated server and want to use the domain name for emails. So you need to setup a mail server using an smtp server and an imap/pop server.
This tutorial shows you how to setup Postfix (smtp server) and Dovecot (imap/pop server). The task of the smtp server is to accept incoming mails and relay outgoing mails from authorised users on the system.
Whereas Dovecot allows authorized users to access their Inbox and read whatever mails there are.
The Simple Configuration - We are not doing this
In the simplest kind of configuration for Postfix, just specify your domain name "xyz.com" in the "mydestination" configuration parameter then you shall be able to receive mails for
if there is a (linux) user named silver on the system.
This technique is simple but with heavy drawbacks. Firstly you need to create a new unix user account for every new email address we need.
Secondly the users have to login with their system passwords. So this is not a very flexible strategy to setup mail accounts.
Separately you can configure Dovecot to read the incoming mails from the directory where Postfix stores them...
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How to setup a mail server with Postfix and Dovecot on Ubuntu / Debian