Cisco Systems A9014CFD manual 24-22, Routerconfig-pmap-c#bandwidth remaining percent

Chapter 24 Configuring QoS

Understanding QoS

•When you use the bandwidth policy-map class configuration command to configure a class of traffic as a percentage of total bandwidth, it represents the portion of the excess bandwidth of the port that is allocated to the class. This means that the class is allocated bandwidth only if there is excess bandwidth on the port, and if there is no minimum bandwidth guarantee for this traffic class.

Note You can configure bandwidth as percentage of remaining bandwidth only when strict priority (priority without police) is configured for another class in the output policy map.

Note You cannot configure bandwidth and traffic shaping (shape average) or priority queuing (priority) for the same class in an output policy map.

This example shows how the classes outclass1, outclass2, and outclass3 and class-defaultget a minimum of 40%, 20%, 10%, and 10% of the total bandwidth. Any excess bandwidth is divided among the classes in the same proportion as rated in the CIR.

Router(config)# policy-map out-policy

Router(config-pmap)# class outclass1

Router(config-pmap-c)# bandwidth percent 40

Router(config-pmap-c)# exit

Router(config-pmap)# class outclass2

Router(config-pmap-c)# bandwidth percent 20

Router(config-pmap-c)# exit

Router(config-pmap)# class outclass3

Router(config-pmap-c)# bandwidth percent 10

Router(config-pmap-c)# exit

Router(config-pmap)# class class-default

Router(config-pmap-c)# bandwidth percent 10

Router(config-pmap-c)# exit

Router(config-pmap)# exit

Router(config)# interface gigabitethernet 0/1

Router(config-if)#service-policy output out-policy

Router(config-if)# exit

Note When you configure CIR bandwidth for a class as a percentage of the total bandwidth, any excess bandwidth remaining after servicing the CIR of all the classes in the policy map, is divided among the classes in the same proportion as the CIR rates. If the CIR rate of a class is configured as 0, that class is also not eligible for any excess bandwidth and as a result receives no bandwidth.

This example shows how to allocate the excess bandwidth among queues by configuring bandwidth for a traffic class as a percentage of remaining bandwidth. The class outclass1 is given priority queue treatment. The other classes are configured to get percentages of the excess bandwidth if any, after servicing the priority queue; outclass2 is configured to get 20 percent, outclass3 to get 30 percent, and the class class-defaultto get the remaining 50 percent.

Router(config)# policy-map out-policy

Router(config-pmap)# class outclass1

Router(config-pmap-c)# priority

Router(config-pmap-c)# exit

Router(config-pmap)# class outclass2

Router(config-pmap-c)#bandwidth remaining percent 20

Router(config-pmap-c)# exit

Router(config-pmap)# class outclass3

Router(config-pmap-c)#bandwidth remaining percent 30

Router(config-pmap-c)# exit

Router(config-pmap)# exit

	Cisco ASR 901 Series Aggregation Services Router Software Configuration Guide
24-22	OL-23826-09