Configure Ubuntu 16.04 with LEMP to send emails for multiple websites
I am trying to configure my droplet running Ubuntu 16.04 with LEMP stack to send emails for the websites that I host for things like user registration, order status, etc.
I host several different and unrelated websites on the same server and the problem is that every configuration I have tried limits the @domain.com that the outbound emails are shown as being from. This is problematic for me as I need the email to be from the domain relative to the website that sent the email.
Perhaps I am not asking the correct question, but I haven't found anything on how to accomplish this besides set up a complicated and dedicated mail server for the purpose, which is beyond my needs.