System information

Configuring the Switch
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CLI – The following example shows how to change the CoS assignments.
* Mapping specific values for CoS priorities is implemented as an interface configuration
command, but any changes will apply to the all interfaces on the switch.
Enabling CoS
Enable or disable Class of Service (CoS). Command Attributes
• Traffic Classes – Click to enable Class of Service. (Default: Enabled)
Web – Click Priority, Traffic Classes Status.
Figure 3-86 Enable Traffic Classes
Selecting the Queue Mode
You can set the switch to service the queues based on a strict rule that requires all
traffic in a higher priority queue to be processed before lower priority queues are
serviced, or use Weighted Round-Robin (WRR) queuing that specifies a relative
weight of each queue. WRR uses a predefined relative weight for each queue that
determines the percentage of service time the switch services each queue before
moving on to the next queue. This prevents the head-of-line blocking that can occur
with strict priority queuing.
Command Attributes
• WRR - Weighted Round-Robin shares bandwidth at the egress ports by using
scheduling weights 1, 2, 4, 8, for queues 0 through 3 respectively. (This is the
default selection.)
• Strict - Services the egress queues in sequential order, transmitting all traffic in the
higher priority queues before servicing lower priority queues.
Console(config)#interface ethernet 1/1 4-114
Console(config-if)#queue cos-map 0 0 4-186
Console(config-if)#queue cos-map 1 1
Console(config-if)#queue cos-map 2 2
Console(config-if)#end
Console#show queue cos-map ethernet 1/1 4-188
Information of Eth 1/1
CoS Value: 0 1 2 3 4 5 6 7
Priority Queue: 0 1 2 1 2 2 3 3
Console#