internal Windows smtp server sending to Exchange local domain
Posted on 2011-04-18
I've got an Exchange 2003 server (EXCH03) in an Active Directory domain (InternalDomain.local) that is responsible for an internet domain name (mydomain.com).
I have another server (UTILITY) in the network that is joined to InternalDomain.local, and runs SMTP as a mail server for some miscellaneous processes (e.g., a NAS box has SMTP settings pointing to UTILITY for unauthenticated relay).
The SMTP service has no problem sending mail to external recipients.
The UTILITY server does not forward mail to the Exchange server for local users with the internet domain as the recipient address. There is no Domain listed in IIS on UTILITY for mydomain.com (only InternalDomain.local).
I have split dns for mydomain.com, with an MX record on the internal zone pointing to the Exchange server, and nslookup from UTILITY successfully finds the MX. The messages simply sit in the Queue folder on UTILITY.
The NAS is set to send mail to myAddress@gmail.com (external) and to firstname.lastname@example.org (my address on the Exchange server).
The SMTP log on UTILITY shows the mail come in from NAS for each rcpt.
There is an outgoing smtp for myAddress@gmail.com
There is no connection (in the smtp log) to EXCH03 for email@example.com