Priority - Cisco ME 3400 Command Reference Manual

priority

priority
Use the priority policy-map class configuration command to configure class-based priority queuing for
a class of traffic belonging to an output policy map. The switch supports strict priority queuing or
priority used with the police policy-map command. Use the no form of this command to remove a
priority specified for a class.
Note When the police command is used with the priority policy-map class command for unconditionally
rate-limiting the priority queue, burst size values are not supported for the police command.
Syntax Description This command has no arguments or keywords.
Defaults No policers are defined.
Command Modes
Policy-map class configuration
Command History Release
12.2(25)EX
Usage Guidelines
When used by itself (not followed by the police policy-map command), the priority command assigns
traffic to a low-latency path and ensures that packets belonging to the class have the lowest possible
latency. With strict priority queuing, packets in the priority queue are scheduled and sent until the queue
is empty.
You should exercise care when using the priority command without the policy command. Excessive use
Note
of strict priority queuing might cause congestion in other queues.
You can use priority with the police {rate-bps | cir cir-bps} policy-map command to reduce the
bandwidth used by the priority queue. This is the only form of policing that is supported in output policy
maps. Using this combination of commands configures a maximum rate on the priority queue and allows
you to use the bandwidth and shape average policy-map commands for other classes to allocate traffic
rates on other queues.
When you use the police command with the priority command in an output policy, the police rate range
Note
is 64000 to 1000000000 bps, even though the range that appears in the command-line help is 8000 to
1000000000. Configured burst size is ignored when you try to attach the output service policy.
Cisco ME 3400 Ethernet Access Switch Command Reference
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priority
no priority
Modification
This command was introduced.
Chapter 2 Cisco ME 3400 Ethernet Access Switch Cisco IOS Commands
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