External Relay Setup for Local Domain


Aug 31, 2008
I think I have reached a dead end. My requirements are simple I hope.

1. I need to enable relay for an external host with a fixed ip, say app.domain.com

2. app.domain.com is also registered as a (sub)domain on cPanel to enable domain forwarding so that the app.domain.com host itself never has to process any incoming SMTP traffic. domain.com is also registered with cPanel.

3. app.domain.com requires SMTP relay host but it does not support authenticated relay.

When I enabled the app.domain.com in /etc/alwaysrelay by IP I get this error:

H=app.domain.com [x.x.x.x] F=<[email protected]> rejected RCPT <[email protected]>: Forged HELO: you are not app.domain.com our local domain and you are not allowed to use
as per RFC Standards.

That I think is because app.domain.com is of course registered with cPanel. But it has to be to enable domain forwarding. Is there a way out of this?