Hello again to the linux questions community.
I am seeking advice as to how I should set up a High Volume Mail Server with sendmail. The unit has 3 Intel 1000 Pro NIC's that I have already set up, and are working fine as far as connectivity is concerned. Two of them have static addresses, and one (that I use for administrative duties only) is DHCP. Perhaps in the future I'll set it up as a failsafe device.
Here is the desired outcome. I would like to set up the machine so one of the NIC's exclusively sends mail to the outside relay. I dont want it to accept any traffic aside from whatever is needed for reverse dns lookups (if any?). The second NIC I would like to accept incoming SMTP connections.
I have already put a line in my .mc reading
If I am not mistaken, this will tell sendmail to only listen on the one adapter for smtp connections. To limit the connectivity on the other device, should I use IPTables? Any advice? An alternate suggestion on how I should set up this system? Is it sendmail that stipulates the outgoing device, or is it another daemon of sorts?
Any advice that you are willing to give, I'll listen to.