Alexander Hoogerhuis wrote:

I've read documentation (obviously not the right parts) and googled, but I can't seem how to solve this simple problem:

I have a machine running postfix/dovecot and using virtual domains, delivery happens with dovecot's LDA. I also have an Exchange machine that I have to house some of the users of a given domain.

How can I tell either postifx in general or dovecot's LDA that whatever specific user that cannot be found in the virutal setup can be pawned off to a given relay-server which will sort it out?

This is for postfix. The answer depends on which addresses would be accepted (not rejected nor bounced) by the relay-server. In short, will it accept all addresses? would I get a bounce if I send to arbitrayaddress@domain.example?

followup on the postfix users list.