To force a client to validate its logon against a specific domain controller, do the following:
Open Registry Editor.
Navigate to the path below:
HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesNetBTParameters
Create a New > DWORD value with the name NodeType and press ENTER.
Double-click on the new value and set it to 4 (this sets the network to an M-mode/mixed which means it will perform a broadcast before querying name servers for resolution). By default, a system is 1 if no WINS servers are configured (B-node/broadcast) or 8 if at least one WINS server is configured (H-node/queries name resolution first then broadcasts)