Specifications

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Catalyst 4500 Se ries S wit ch C is co IO S C om mand R efer ence —Re lease I OS XE 3 .3.0 XO(1 5.1 (1)XO)
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Chapter 2 Cisco IOS Commands for the Catalyst 4500 Series Switches
priority
priority
To enable the strict priority queue (low-latency queueing [LLQ]) and to give priority to a class of traffic
belonging to a policy map attached to a physical port, use the priority policy-map class configuration
command. To return to the default setting, use the no form of this command.
priority
no priority
Syntax Description This command has no arguments or keywords.
Defaults The strict priori ty queue is disabled.
Command Modes Policy-map class configuration mode
Usage Guidelines Use the priority command only in a policy map attached to a physical port. You can use this command
only in class-level classes, you cannot use this command in class c lass-default.
This command configures LLQ and prov ides strict-priority queueing. Strict-pr iority queueing ena bles
delay-sensitive data, such as voice, to be sent before packets in other queues are sent. The priority queue
is serviced first until it is empty.
You cannot use the bandwi dt h, dbl , and the shape policy-map clas s configuration commands w ith the
priority policy-map class configuration command in the same class within the same policy map.
However, you can use these commands in the same p olicy map.
You can use police or set class configuration commands with the priority police-map class configuration
command .
If the priority queuing class is not rate limited, you cannot use the bandwidth command, you can use the
bandwidth remaining percent command instead.
Examples This example shows how to enable the LLQ for the policy map called policy1:
Switch# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Switch(config)# policy-map policy1
Switch(config-pmap)# class voice
Switch(config-pmap-c)# priority
You can verify your settings by entering the show policy-map privileged EXEC command.