Virtual Machine Network Health not working

Server 2012 R2 is supposed to have a feature which detects when the public LAN connection used to get into the VM's becomes unavailable, this is supposed to kick in around 60 seconds after it being unavailable. however, I have tried to test this by physically unplugging the network cable, and disabling the network adapter in ncpa.cpl and the virtual machine doesn't seem to live migrate to the other node. the settings for the network adapter in the virtual machine configuration has the "protected network" box checked by default. is there something else we need to check/configure here?

it looks like it tries to migrate but fails, the message in the information details state:

thanks

Steve