Cisco Catalyst 3750 Software Configuration Manual page 572

Configuring Hierarchical QoS
Command
Step 7 random-detect
exponential-weighting-constant weight
Step 8
exit
Step 9
exit
Step 10
interface interface-id
Step 11 service-policy output policy-map-name
Step 12
end
Step 13
show policy-map [policy-map-name [class
class-map-name]]
or
show policy-map interface interface-id
Step 14 copy running-config startup-config
To delete an existing policy map, use the no policy-map policy-map-name global configuration
command. To delete an existing class, use the no class class-name policy-map configuration command.
To return to the default bandwidth, use the no bandwidth policy-map class configuration command. To
disable DSCP-based WRED, use the no random-detect dscp-based policy-map class configuration
command. To return to the default WRED settings, use the no random-detect dscp dscp policy-map
class configuration command.
This example shows how to configure a class-level policy called policy10. Class c1 has these
characteristics: a minimum of 2000 kbps of bandwidth is expected to be delivered to this class in the
event of congestion, and a weight factor of 10 is used to calculate the average queue size. To avoid
congestion, DSCP-based WRED packet drop is used instead of tail drop. The minimum threshold for
DSCP value 8 is 24, the maximum threshold is 40, and the mark-probability denominator is 512.
Switch(config)# class-map c1
Switch(config-cmap)# match ip dscp 8
Switch(config-cmap)# exit
Switch(config)# policy-map policy10
Switch(config-pmap)# class c1
Switch(config-pmap-c)# bandwidth 2000
Switch(config-pmap-c)# random-detect dscp-based
Switch(config-pmap-c)# random-detect exponential-weighting-constant 10
Switch(config-pmap-c)# random-detect dscp 8 24 40 512
Switch(config-pmap-c)# exit
Switch(config-pmap)# exit
Switch(config)# interface gigabitethernet1/1/1
Switch(config-if)# switchport trunk encapsulation isl
Switch(config-if)# switchport mode trunk
Switch(config-if)# service-policy output policy10
Catalyst 3750 Metro Switch Software Configuration Guide
26-92
Purpose
(Optional) Configure the exponential weight factor for the average
queue-size calculation for WRED. The range is 1 to 16. The default
is 9.
Return to policy-map configuration mode.
Return to global configuration mode.
Specify an ES port to attach to the policy map, and enter interface
configuration mode.
Specify the egress policy-map name, and apply it to the ES port.
Only one policy map per port is supported.
Return to privileged EXEC mode.
Verify your entries.
(Optional) Save your entries in the configuration file.
Chapter 26 Configuring QoS
78-15870-01