Cisco IE 4000, Software Configuration Manual

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Configuring QoS
Configuring QoS

You cannot configure priority queuing without policing for a traffic class when class-based shaping ( shape average )
or CBWFQ ( bandwidth ) is configured for another class within the output policy-map.

When you configure priority queuing without policing for a traffic class, you can only configure the other queues for
sharing by using the
bandwidth remaining percent policy-map class configuration command to allocate excess
bandwidth. This command does not guarantee the allocated bandwidth, but does ensure the rate of distribution.
Beginning in privileged EXEC mode, follow these steps to configure a strict priority queue:
After you have created an output policy map, you attach it to an egress port. See Attaching a Traffic Policy to an Interface,
page 609 .
Use the no form of the appropriate command to delete an existing policy map or class map or to cancel strict priority
queuing for the priority class or the bandwidth setting for the other classes.
This example shows how to configure the class out-class1 as a strict priority queue so that all packets in that class are
sent before any other class of traffic. Other traffic queues are configured so that out-class-2 gets 50 percent of the
remaining bandwidth and out-class3 gets 20 percent of the remaining bandwidth. The class class-default receives the
remaining 30 percent with no guarantees.
Switch(config)#
policy-map policy1
Switch(config-pmap)# class out-class1
Switch(config-pmap-c)# priority
Command Purpose
1. configure terminal Enter global configuration mode.
2. class-map class-map-name Create classes for three egress queues. Enter match conditions
classification for each class.
3. policy-map policy-map-name Create a policy map by entering the policy map name, and enter
policy-map configuration mode.
4. class class-map-name Enter the name of the priority class (created by using the class-map
global configuration command), and enter policy-map class
configuration mode for the priority class.
5. priority Set the strict scheduling priority for this class.
Note: Only one unique class map on the switch can be associated with a
priority command. You cannot configure priority along with any other
queuing action ( bandwidth or shape average ).
6. exit Exit policy-map class configuration mode for the priority class.
7. class class-map-name Enter the name of a nonpriority class, and enter policy-map class
configuration mode for that class.
8. bandwidth remaining percent value Set output bandwidth limits for the policy-map class as a percentage of
the remaining bandwidth. The range is 1 to 100 percent.
9. exit Exit policy-map class configuration mode for the class
10. exit Return to global configuration mode.
11. interface interface-id Enter interface configuration mode for the interface to which you want to
attach the policy.
12. service-policy output
policy-map-name
Attach the policy map (created in Step 3) to the egress interface.
13. end Return to privileged EXEC mode.
14. show policy-map Verify your entries.
15. copy running-config startup-config (Optional) Save your entries in the configuration file.