There are many docker images available for postfix, but I could not fine one which will satisfy my needs. I've been using it for last year or so, so decided to release it publicly.
If configured incorrectly, this can become an open relay SMTP server, so hosting it on public interfaces is not advisable.
If you have devices which can send notifications, but does not support SMTP authentication, or SMTP authentication is broken -- relay SMTP server can help. It will relay via upstream SMTP server. Received header will be hidden, so your internal network information won't leak.
Modify docker-compose.yml with your settings. Then:
docker-compose up -dConfigure email client to send email via your local SMTP server.
Generate Postfix SMTP server EDH parameters for improved security against pre-computation attacks:
openssl dhparam -out dh512.tmp 512 && mv dh512.tmp dh512.pem
openssl dhparam -out dh2048.tmp 2048 && mv dh2048.tmp dh2048.pemRequest SSL certificate from Let's Encrypt using lego or any other tool, and save certificate as cert.pem and private key as key.pem in the root of the repository.
Some ideas where found and sometimes copied from the following projects:
This is open source project. If you find a bug or have a suggestion, please open issue, or submit a pull request.