Hi all,

I have an exchange server that is hosting a few domains email. Unfortunately the anti-spam features on exchange aren't particuarly great so i'm installing postfix and spamassasin to receive email, filter out spam and relay it to exchange.

I am using transport maps and a relay domains file to specify which domains i want to allow relaying for.

This appears to be working ok, however, if i telnet to the postfix server and try to send email to a domain that isn't in my relay domains file, it still tries to send the email and doesnt reject the relay.

Am I missing some extra config I need for this?

Many thanks

Sounds like yes.

Is your telnet test from a "trusted" sender? (mynetworks or logged in or such)

A "non-local" sender to a "non-local" recipient should be rejected by default (by 'reject_unauth_destination' directive).

You'll probably need to post some specific examples as the details matter.