Sendmail question
 

I currently have a web server that does incoming and outgoing email as well. I have one nic eth0 and will be installing a second nic eth1 configured with a separate IP.

How do I send email out thru eth1 instead of eth0?

IP traffic is sent from a source IP address. A source IP is selected based on the address of the next-hop router and the address(es) the service in question is bound to, and the interface is then selected based on that address.

If you bind sendmail to the IP address of eth1, it will use that IP address for all communication. Of course, that means inbound mail must also be directed at that address, as no smtp service will be listening on any other address.

Thank you Ser Olmy. I need to reserve Sendmail for incoming and most outgoing.
I am going to install qmail and try to send some email via eth1.