BMR config using 5230 NB appliance

i am new to NB. We have recently configured a 5230 NB appliance which we would like to use for BMR. We enabled BMR on the appliance. I have been reading the BMR admin guide (partially) which indicates that we need to have a server to act as the BMR boot server.

So the question is if I have the appliance do I need to have a seperate boot server or will the appliance be that server?