Configuring User Based Rate Limiting - Cisco 4500M Software Manual

Chapter 29 Configuring QoS

Configuring User Based Rate Limiting

The feature User Based Rate Limiting (UBRL) adopts microflow policing to dynamically learn traffic
flows and rate limit each unique flow to an individual rate. A flow is defined as a five-tuple (IP source
address, IP destination address, IP head protocol field, Layer 4 source and destination ports). Flow-based
policers enable you to police traffic on a per flow basis. Because flows are dynamic, they require
distinguishing values in the class map.
Flow policers (and UBRL) are supported only on the Supervisor Engine V-10GE. Flow policers are
Note
supported only in the input direction and on Layer 3 interfaces. You can configure up to 511 unique flow
policers and can "microflow" police more than 100,000 flows.
When you specify the match flow command with the source-address keyword, each flow with a unique
source address is treated as a new flow. When you specify the match flow command with the
destination-address keyword, each flow with a unique destination address is treated as a new flow. If
the class map used by the policy map has any flow options configured, it is treated as a flow-based policy
map.
To configure the flow-based class maps and policy maps, perform this task:
Command
Step 1
Switch(config)# class-map match-all class_name
Step 2
Switch(config-cmap)# match flow ip {source-address |
destination-address}
Step 3
Switch(config-cmap)# end
Step 4
Switch# show class-map class-name
This example shows how to create a flow-based class map associated with a source address:
Switch(config)# class-map match-all c1
Switch(config-cmap)# match flow ip source-address
Switch(config-cmap)# end
Switch#
Switch# show class-map c1
Class Map match-all c1 (id 2)
Match flow
This example shows how to create a flow-based class map associated with a destination address:
Switch(config)# class-map match-all c1
Switch(config-cmap)# match flow ip destination-address
Switch(config-cmap)# end
Switch#
Switch# show class-map c1
Class Map match-all c1 (id 2)
Match flow
OL-6696-01
ip source-address
ip destination-address
Purpose
Creates a named class map.
Specifies the key fields of the flow.
Exits class-map configuration mode.
Verifies the configuration.
Software Configuration Guide—Release 12.2(25)EW
Configuring QoS
29-35