System information

Class of Service Configuration
3-99
CLI – The following example shows how to change the CoS assignments to a
one-to-one mapping.
* 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.
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, 4, 16, and 64 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.
Web – Click Priority, Queue Mode. Select Strict or Wrr, then click Apply.
CLI – The following sets the queue mode to strict priority service mode.
Console(config)#interface ethernet 1/1 4-86
Console(config)#queue cos-map 0 0 4-148
Console(config)#queue cos-map 1 1
Console(config)#queue cos-map 2 2
Console(config)#exit
Console#show queue cos-map ethernet 1/1 4-149
Information of Eth 1/1
Traffic Class : 0 1 2 3 4 5 6 7
Priority Queue: 0 1 2 1 2 2 3 3
Console(config)#queue mode strict 4-149
Console(config)#exit
Console#show queue mode 4-149
Queue mode: strict
Console#