Mainly this server is going to be used for Delta Chat.
This web server is only here for certbot to verify and renew SSL certificates.
How to make your own Delta Chat Email Server and compete with WhatsApp/Signal/Telegram
useradd -m -G mail billy passwd billy
And then add them to the virtual address map like this:
nano /etc/postfix/virtual
Add the address map:
exampleuser@domain.org billy
Ctrl + X to save. Then apply and restart:
postmap /etc/postfix/virtual systemctl restart postfix && systemctl restart dovecot
userdel billy rm -r /home/billy
Also remove them from:
nano /etc/postfix/virtual
Multiple Domains w/ SSL & DKIM
This should fix it:
postmap -F /etc/postfix/vmail_ssl.map && systemctl restart postfix && systemctl restart dovecot && systemctl restart opendkim
Warrant Canary: No warrants have been served for this server