I am attempting to apply a simple CBWFQ/LLQ policy for voice traffic over an ATM UBR configured as a subinterface. When I apply the service-policy to the PVC on the subinterface it doesn't stick. A warning is logged saying that there is no available bandwidth to reserve. From other reading it seems this is directly related to PVC being configured as a UBR. Does this mean no QoS can be applied to a UBR? If not, then how must this be done?
Here is a sanitized snippet of the config in question:
interface ATMx/x.x point-to-point
ip address x.x.x.1 255.255.255.252
protocol ip x.x.x.2 broadcast
Thanks in advance,