Oversubscription And Hierarchical Policies; Configuring Oversubscription - Cisco 10000 Series Configuration Manual

Oversubscription and Hierarchical Policies

Oversubscription and Hierarchical Policies
You can create a hierarchical policy to manage traffic within a virtual circuit. When such a configuration
exists, the router allocates the physical pipe into smaller pipes. Instead of creating a single versatile time
management scheduler (VTMS) link for the physical interface, each parent policy map has a VTMS link.
Previously, the sum of the bandwidths of the parent policies had to be less than the bandwidth of the
physical link. With interface oversubscription, the sum of the parent policies can oversubscribe the link.
For more information about hierarchical policies, see
Levels."
Example 15-1
a hierarchical policy. In the example, the traffic class named class1 is policed at 60 percent of the total
transmission capacity and the class named class2 is allocated 45 percent of the total bandwidth.
Therefore, the total requested bandwidth exceeds the link bandwidth.
Example 15-1 Oversubscribing a Link Using Nested Policies
Router(config)# class-map match-all class1
Router(config-cmap)# match access-group1
Router(config-cmap)# exit
Router(config)# class-map match-all class2
Router(config-cmap)# match access-group2
Router(config-cmap)# exit
Router(config)# policy-map dlci-103 [child policy]
Router(config-pmap)# class class1
Router(config-pmap-c)# priority
Router(config-pmap-c)# police percent 60
Router(config-pmap-c)# class class2
Router(config-pmap-c)# bandwidth percent 45
Router(config-pmap-c)# exit
Router(config-pmap)# policy-map shape-2meg-dlci-103 [parent policy]
Router(config-pmap)# class class-default
Router(config-pmap-c)# shape 2000
Router(config-pmap-c)# service-policy dlci-103 [child policy]
Router(config-pmap)# exit
Router(config)# interface serial 5/0/0.1 point-to-point
Router(config-subif)# ip address 10.1.0.2 255.255.255.252
Router(config-subif)# service-policy output shape-2meg-dlci-103 [attaches parent policy]
Router(config-subif)# frame-relay interface-dlci 103
For more information about hierarchical policies, see
Levels."

Configuring Oversubscription

To configure oversubscription on ATM, Frame Relay, and 802.1Q VLAN virtual circuits, perform any
of the following configuration tasks:
•
•
•
Cisco 10000 Series Router Quality of Service Configuration Guide
15-10
shows how to oversubscribe a Frame Relay subinterface when defining QoS behavior in
Oversubscribing ATM VBR-nrt VCs, page 15-11
Oversubscribing Frame Relay PVCs, page 15-11
Oversubscribing 802.1Q VLANs, page 15-17
Chapter 15 Oversubscribing Physical and Virtual Links
Chapter 13, "Defining QoS for Multiple Policy
Chapter 13, "Defining QoS for Multiple Policy
OL-7433-09