How to specify address for SMTP service

[TexExpat]

On my Exchange 2000 Server, how can I tell the SMTP service which address (that is, which network interface) to use to send SMTP messages?

My Exchange Server is dual homed with one NIC connected to the internal (192.168.x.y) network and the other configured with a public IP address and connected to our Internet router. The internal NIC is also configured with a default gateway that can see a NAT server, so the Exchange Server can actually get to the Internet through either server. I have just found that SMTP messages are being sent through the NAT server rather than through the NIC with the public IP address. Thus, I get some messages returned because the receiving server cannot perform a reverse DNS lookup against the IP address listed in the header of the message.

I tried setting the properties of the Default SMTP Virtual Server to use only the public address, then restarted the SMTP service. However, my messages are still going out through the internal NIC and the NAT server rather than through the public interface.

Short of removing the default gateway from the internal NIC configuration, how can I get SMTP to send mail out through only the NIC with the public address?

Thank you very much for your help.

 

[nhidalgo]

why not set the default gateway of your exchange server to your internet router and then use a route add command for your internal network. so that anything not going to your internal lan route out via the internet router.

Nick