" I always just use split horizon DNS, and put everything under the corporate domain name, thus eliminating the problem."
I have something like that at home, a registered domain name example.com and a portion *.home.example.com that was only resolvable from my lan.
Then, a few months back, I upgraded to the new Linux Mint LTS, which did all queries simultaneously to my ISP (fallback DNS) and my LAN DNS, using the first response. Sometimes the ISP was faster, resulting in 'nonexistent host' errors.
It took me an hour to figure out what was wrong and how to repair it (networkmanager.conf, disable dnsmasq). Sigh. I wasn't the first to have this problem. The devs didn't really see the problem. https://bugs.launchpad.net/ubu...