Sending an email using Basic SMTP server

[qlands]

I'm running the Basic SMTP server and trying to send an email using Python + SMTPLib but I always get "Connection refused" Do you have any examples on how to send an email with the Basic SMTP server?

[khromov]

@qlands Can you check whether the IP address you are trying to send the email from is whitelisted according to RELAY_NETS? (See at the bottom of https://github.com/BytemarkHosting/docker-smtp#environment-variables )

[gonzalodiaz]

What should be the RELAY_NETS to send emails to gmail? Thanks

[khromov]

@gonzalodiaz RELAY_NETS is not the addresses you send to, it's the ip ranges that the SMTP server will accept mail from, and any machines you run in docker needs to run within those ip ranges. You can find the default ranges here: https://github.com/BytemarkHosting/docker-smtp#environment-variables

If your ranges are not listed, you need to add your docker ip ranges via RELAY_NETS.

[coreyog]

I tried setting RELAY_NETS to 0.0.0.0/0, 127.0.0.1/32, and <my internal IP>/32 and I can't get any program from outside the container to connect.

I tried getting a shell inside the container, apt install netcat, nc localhost 25 and did all the HELO'ing myself and successfully got an email to send. I feel like something is up with how RELAY_NETS works.

[khromov]

@coreyog Did you try netcat from another docker container in the same docker-compose.yml? (I'm assuming you're using docker-compose with multiple containers of which the smtp one is one of them).

If you have a different setup, please share it.

[spdbel]

use ports:
- 127.0.0.1:25:25