Usage of DNS Forwarders vs External DNS Servers

[techseek]

Hello
I demoted an 03 DC and removed the DNS role. I then started
getting some event id 2012 "SMTP could not connect to DNS server"...
So i looked around and found the "down" server IP configured as an external DNS server in SMTP protocol (system mngr) settings. i know that our DNS has our ISP's external DNS servers configured in "Forwarders". So the question for me is...Do I need any external DNS servers configured in SMTP. What I had there were internal IP's which sorta contradicts the "external" designation anyways. Further, we've been operating with those settings for years with no problems whatsoever. I'd like to clear this up to have a cleaner config.

Thanks

 

[ShackDaddy]

You don't need it configured in SMTP, that's a non-standard configuration and I very rarely ever see it. That might only be the case in an environment in which most internal servers aren't give internet access so they point normally at an internal DNS server that won't resolve queries for external names. In that case you would configure that SMTP DNS so that the mail system could resolve external names.

Dave Shackelford
ThirdTier.net
TrainSignal.com