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Catalyst 3550 Multilayer Switch Software Configuration Guide
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Chapter 20 Configuring QoS
Configuring QoS
Classifying, Policing, and Marking Traffic by Using Aggregate Policers
By using an aggregate policer, you can create a policer that is shared by multiple traffic classes within
the same policy map. However, you cannot use the aggregate policer across different policy maps or
interfaces.
Beginning in privileged EXEC mode, follow these steps to create an aggregate policer:
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
mls qos
Enable QoS on the switch.
Step 3
mls qos aggregate-police
aggregate-policer-name rate-bps
burst-byte exceed-action {drop |
policed-dscp-transmit}
Define the policer parameters that can be applied to multiple traffic
classes within the same policy map.
By default, no aggregate policer is defined.
You can configure up to 128 policers on ingress Gigabit-capable
Ethernet ports, up to 8 policers on ingress 10/100 Ethernet ports, and
up to 8 policers on egress ports.
•
For aggregate-policer-name, specify the name of the aggregate
policer.
•
For rate-bps, specify average traffic rate in bits per second (bps).
The range is 8000 to 2000000000.
•
For burst-byte, specify the normal burst size in bytes. The range is
8000 to 512000000.
•
(Optional) Specify the action to take when the rates are exceeded.
Use the exceed-action drop keywords to drop the packet. Use the
exceed-action policed-dscp-transmit keywords to mark down the
DSCP value (by using the policed-DSCP map) and send the packet.
For more information, see the
“Configuring the Policed-DSCP
Map” section on page 20-41
.
Step 4
class-map class-map-name [match-all |
match-any]
Create a class map to classify traffic as necessary. For more
information, see the
“Classifying Traffic by Using Class Maps” section
on page 20-30
.
Step 5
policy-map policy-map-name
Create a policy map by entering the policy map name, and enter
policy-map configuration mode.
For more information, see the
“Classifying, Policing, and Marking
Traffic by Using Policy Maps” section on page 20-32
.
Step 6
class class-map-name [access-group
acl-index-or-name | dscp dscp-list |
precedence ip-precedence-list]
Define a traffic classification, and enter policy-map class configuration
mode.
For more information, see the
“Classifying, Policing, and Marking
Traffic by Using Policy Maps” section on page 20-32
.
Step 7
police aggregate aggregate-policer-name
Apply an aggregate policer to multiple classes in the same policy map.
For aggregate-policer-name, enter the name specified in Step 3.
Step 8
exit
Return to global configuration mode.
