I have a PXI-8231 ethernet card with a PXI-8106 controller runing in Real Time ver 8.2 both MAC addresses show up when the RT system boots the secondary port shows to be disabled. I am unabel to enable this port in MAX the option is grayed out.
LabVIEW RT supports only one Ethernet interface at a time, and it will select the faster Ethernet interface as its primary. There is more information about this here.