All my Macs are connected to the LAN (wired) and to a isolated wifi network.
Some Macs are registering in the DNS with the IP of the Wifi network instead of the IP from the LAN (wired network).
Can you tell me how to force the Macs to register in the DNS with the LAN IP (wired) instead of Wifi?
I know how to do this on Windows clients but not on the Macs.
Go into Network System prefs and select "set order of services" from the gear menu below the list of services.
Drag Ethernet above WiFi.
OS X will use the top-most Service that has an Internet connection as the Internet Service.