Simple and light container for a receiving SMTP server without relay capability.
Only configured addresses can receive mail and everything is consolidated into a single user.
DOMAIN- FQDN for the server. Used for the domain part of the accepted emailsACCOUNTS- Comma-separated list of aliases for the single account
No volumes are defined. If you want persistent spool storage then mount
/home/smtp/Maildir outside of the container.