I have a Windows 2008 server that has three IP bound to the NIC. I can select which IP Windows SMTP listens to, but I want to also set the IP address used when mail is sent. Where would I set which outbound IP to use when sending email?
Without using real IPs, here is an example what I have setup. Three IPs associated with the server: 10.0.0.1 10.0.0.2 10.0.0.3
I setup the binding on 10.0.0.2 for port 25 in the SMTP server settings, so that it is the only IP that will respond for inbound. When I look at the email header from an email sent from that server, it lists the server with an address of 10.0.0.3. I would like it to use 10.0.0.2 so that when reverse DNS is performed, it maps back correctly.
A specific smtp server instance only binds to one address. If you want to separate them then you need to fire up a second server, but it'll have to bind to a different port (which shouldn't be that big of a problem for outgoing traffic).