Enterasys Networks X-Pedition XSR CLI - Manual (Page 486)

Policy-Map Commands
12-90 Configuring Quality of Service
Example
The following example defines a traffic class using the class-map command and match criteria
from the traffic class with the Traffic Policing configuration, which is configured in the service
policy using the
policy-map command. The service-policy command is then used to attach
this service policy to the interface.
In this example, traffic policing is configured with the average rate of 8000 bits per second and the
normal burst size at 1200 bytes and an excess burst of 2000 bytes for all packets leaving F1/0:
XSR(config)#class-map access-match
XSR(config-cmap)#match access-group 1
XSR(config)#policy-map police-setting
XSR(config-pmap)#class access-match
XSR(config-pmap-c)#police 8000 1200 2000 conform-action transmit
exceed-action drop
XSR(config>)interface fastethernet 1/0
XSR(config-if)#service-policy output police-setting
priority
This command gives priority to a class of traffic belonging to a policy map. It configures low
latency queueing, providing strict Priority Queues (PQ) over Class‐based Weighted Fair Queueing
(CBWFQ). Strict PQ allows delay‐sensitive data such as voice to be de‐queued and sent before
packets in other queues are dequeued.
The burst argument specifies the burst size and, as such, configures the network to accommodate
temporary bursts of traffic. The default burst value, which is computed as 1 second of traffic at the
configured bandwidth rate, is used when the burst argument is not specified.
Priority queues can be reserved by absolute bandwidth with these settings: high, medium, low and
normal.
Syntax
priority priority-level bandwidth-kbps [burst]
Syntax of the “no” Form
Remove a previously specified priority specified for a class with the no form of this command:
no priority
Note: The bandwidth and priority commands cannot be used in the same class, within the
same policy map, but they can be used together in the same policy map. They cannot be configured
for class-default. Class-default is always defined as fair queue.
priority level Specifies the priority queue: high, medium, low or normal. Normal
priority has the least precedence.
bandwidth-kbps Guaranteed allowed bandwidth for priority traffic. Beyond the
guaranteed bandwidth, priority traffic will be dropped to ensure that
non‐priority traffic is not starved. Range: 1 to 100,000 kbps.
burst Sets the burst size, ranging from 32 to 2,000,000 bytes.