Class of Service Commands

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4
Default Setting
Weights 1, 2, 4, 8 are assigned to queues 0-3 respectively.
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
• WRR controls bandwidth sharing at the egress port by defining scheduling
weights.
• WRR uses a relative weight for each queue which determines the number of
packets the switch transmits every time it services a queue before moving on
to the next queue. Thus, a queue weighted 8 will be allowed to transmit up to
8 packets, after which the next lower priority queue will be serviced according
to it’s weighting. This prevents the head-of-line blocking that can occur with
strict priority queuing.
Example
This example shows how to assign WRR weights to priority queues 0 - 2:
Related Commands
show queue bandwidth (4-249)

queue cos-map

This command assigns class of service (CoS) values to the priority queues (i.e.,
hardware output queues 0 - 3). Use the no form set the CoS map to the default
values.
Syntax
queue cos-map queue-id [cos1 ... cosn]
no queue cos-map
•queue-id - The ID of the priority queue.
Ranges are 0 to 3, where 3 is the highest priority queue.
•cos1 .. cosn - The CoS values that are mapped to the queue ID. It is a
space-separated list of numbers. The CoS value is a number from 0 to 7,
where 7 is the highest priority.
Console(config)#interface ethernet 1/3
Console(config-if)#queue bandwidth 6 9 12
Console(config-if)#