Iredadmin / Postfix: SMTP AUTH is required for users under this sender domain

Root cause

This is because the sending server IP is not listed in the SPF record, but if this has been done by adding the server IP to the SPF record, configuration settings can be made in /opt/iredapd/settings.py by adding the ALLOWED_FORGED_SENDERS parameter which contains the sender's domain name.

Solution

This can be done by adding the ALLOWED_FORGED_SENDERS parameter to /opt/iredapd/settings.py using the following method.

$ nano /opt/iredapd/settings.py

Add ALLOWED_FORGED_SENDER at the end of file configuration.

ALLOWED_FORGED_SENDERS = ["regiapriandi.com"]

Restart Iredmail service

$ systemctl restart iredapd