creating a sub domain for Exchange

[happyhacker]

I have a domain mydomain.org as the external domain. For those users I wish to remain on the ISP server the local users must be able to route emails there. I have tried to set up a CNAME record temp.mydomain.org on my ISP but any emails I send there are "domain not found" even if I send from outside the Exchange (e.g. from home). My plan is to create a contact called "temp" with temp.mydomain.org and use that to divert users emails which are not on the Exchange server. Any idea why this does not work or a way to test it?

The CNAME is "temp.mydomain.org to mydomain.org" TTL 7200.

Thanks for your time.

 

[happyhacker]

I solved this (I think!) by using the external domain as an internal relay and an associated Send connector. This resulted after testing in all email delivery working seemingly well.

The only other thing was replies to emails originating from Exchange in that the "Use as reply address" must be ticked for the correct address in that list or the sender will get a delivery failure if replying from outside.

Comment welcome.

Thanks for your time.