Cisco 10000 Series User Manual

11-30
Cisco 10000 Series Router Quality of Service Configuration Guide
OL-7433-09
Chapter 11 Managing Packet Queue Congestion
Configuring Layer 3 Queue Limit and Drop Policies
Configuration Example for Dropping Packets Based on Discard Class
Example 11-4 shows how to enable discard-class-based weighted random early detection (WRED). In
this example, the configuration of the class map named Silver indicates to classify traffic based on
discard class 3 and 5. Traffic that matches discard class 3 or 5 is assigned to the class named Silver in
the policy map named Premium. The Silver configuration includes WRED packet dropping based on
discard class 5 with a minimum threshold of 500, maximum threshold of 1500, and a
mark-probability-denominator of 200. The QoS policy is applied to PVC 1/81 on point-to-point ATM
subinterface 2/0/0.2 in the outbound direction.
Example 11-4 Configuring Discard-Class-Based WRED
Router(config)# class-map Silver
Router(config-cmap)# match discard-class 3 5
Router(config-cmap)# exit
Router(config)# policy-map Premium
Router(config-pmap)# class Silver
Router(config-pmap-c)# bandwidth percent 30
Router(config-pmap-c)# random-detect discard-class-based
Router(config-pmap-c)# random-detect discard-class 5 500 1500 200
Router(config-pmap-c)# exit
Router(config-pmap)# exit
Router(config)# interface atm 2/0/0
Router(config-if)# atm pxf queuing
Router(config-if)# interface atm 2/0/0.2 point-to-point
Router(config-subif)# pvc 1/81
Router(config-subif-atm-vc)# ubr 10000
Router(config-subif-atm-vc)# service-policy output Premium
Step 4
PRE2, PRE3
Router(config-pmap-c)# random-detect
discard-class discard-class-value
min-thresh-value max-thresh-value
mark-probability-denominator-value
Configures WRED to drop packets based on the discard value you
specify.
discard-class-value is a number that indicates the drop eligibility
of a packet. Valid values are from 0
to 7.
min-thresh-value is the minimum number of packets allowed in
the queue. Valid minimum threshold values are from 1 to 16,384.
max-thresh-value is the maximum number of packets allowed in
the queue. Valid maximum threshold values are from the value of
the minimum threshold to 16,384.
mark-probability-denominator-value is the drop rate. Valid values
are from 1 to 65,535. The default value is 10.
Command Purpose

Cisco 10000 Series Specifications

General

Brand	Cisco
Model	10000 Series
Category	Network Router
Language	English