citizen010/postfix repository overview

⁠docker-postfix - integration into BTCPayServer

A simple "SMTP Only" postfix image.

Emails can be sent everywhere but only from localhost addresses:

• 127.0.0.0/8
• 172.16.0.0./12
• [::1]/128

Start the image and include your hosts DNS entry as below:

docker run -d --name postfix -p 25:25 --restart always citizen010/postfix btcpay.domain.name

Where the first 25 is the local port and the second 25 is the container port.

Remember to change btcpay.domain.name with your own domain name.

This images is available on docker hub⁠ and can be downloaded by running

docker pull citizen010/postfix

⁠How to find out which Postfix version I'm running

SSH into the machine that host your BTCPayServer instance and run:

docker exec -it postfix /bin/bash

postconf mail_version

You should see something like this:

mail_version = 3.3.0

Then exit:

exit

⁠BTCPayServer config

Go to Server Settings -> Email server and fill as below:

• SMTP Server: your external IP address (to find out: curl -s ipinfo.io/ip)
• PORT: 25
• Sender's display name: whatever (e.g. BTCPay Store)
• Sender's email address: [email protected]⁠ (e.g. [email protected]⁠)
• Login: empty
• Password: empty
• Enable SSL: not checked
• Test Email: [email protected]⁠

Press Send Test Email

You should see Email sent to [email protected]⁠, please, verify you received it and then check (also on Spam folder) if a test email was received.

Press Save

If you see an error message (eg. error 4.7.1) double check the parameters and try again.