Red60 DNS settings when used with XG for a red tunnel

You can setup an own DHCP server for your REDs. RED is simply a network cable plugged into your Firewall. 

Apologies, a little new to the red device management - but in normal network speak, there would be a DHCP forwarder statement somewhere.  Any pointers on where that would be - or how the DHCP request would get forwarded into my internal DHCP server?