Class of Service Commands

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queue mode

This command sets the queue mode to strict priority or Weighted Round-Robin
(WRR) for the class of service (CoS) priority queues. Use the no form to restore the
default value.
Syntax
queue mode {strict | wrr}
no queue mode
strict - Services the egress queues in sequential order, transmitting all
traffic in the higher priority queues before servicing lower priority queues.
wrr - Weighted Round-Robin shares bandwidth at the egress ports by using
scheduling weights 1, 2, 4, 8 for queues 0 - 3 respectively.
Default Setting
Weighted Round Robin
Command Mode
Global Configuration
Command Usage
Strict priority requires all traffic in a higher priority queue to be processed
before lower priority queues are serviced.
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
The following example sets the queue mode to strict priority service mode:

switchport priority default

This command sets a priority for incoming untagged frames. Use the no form to
restore the default value.
Syntax
switchport priority default default-priority-id
no switchport priority default
default-priority-id - The priority number for untagged ingress traffic.
The priority is a number from 0 to 7. Seven is the highest priority.
Console(config)#queue mode strict
Console(config)#