Forward all mail with unresolved recipients to host
Posted on 2009-04-08
We're a school that are merging with another school. At present, we are still on two sites however want to have the same e-mail domain. Both schools are connected to the LEA WAN. I've created a new domain, and had the LEA create the domain in their DNS structure. All e-mails for this domain now come to the exchange server on Site A. Great!
I had then planned to have any e-mails that were intended for Site B to be forwarded to Site B's exchange server using the "Forward all mail with unresolved recipients to host" option of the Virtual SMTP server. In this field I have put the IP address of the server in square brackets, i.e. [10.xxx.xxx.xxx] as it is not part of our DNS structure.
I've created recipient policies on the Exchange server at both sites, and made sure that neither have the 'This Exchange server is repsonsible for all mail delivery to this address' ticked.
If I try to e-mail a mailbox on Site B, it does not work. I get an 'unable to relay' message from the LEA mail server. So it appears that the exchange box on Site A is ignoring the 'Forward all mail with unresolved recipients to host' and instead sending the message back out via our LEA connector. Fortunately it is rejected otherwise we'd be in an endless loop!
What have I missed?
Many thanks in advance