Command Line Interface
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4
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
• The precedence for priority mapping is IP Port, IP Precedence or IP DSCP,
and default switchport priority.
• The default priority applies for an untagged frame received on a port set to
accept all frame types (i.e, receives both untagged and tagged frames). This
priority does not apply to IEEE 802.1Q VLAN tagged frames. If the incoming
frame is an IEEE 802.1Q VLAN tagged frame, the IEEE 802.1p User Priority
bits will be used.
• This switch provides eight priority queues for each port. It is configured to use
Weighted Round Robin, which can be viewed with the show queue
bandwidth command. Inbound frames that do not have VLAN tags are
tagged with the input port’s default ingress user priority, and then placed in the
appropriate priority queue at the output port. The default priority for all ingress
ports is zero. Therefore, any inbound frames that do not have priority tags will
be placed in queue 0 of the output port. (Note that if the output port is an
untagged member of the associated VLAN, these frames are stripped of all
VLAN tags prior to transmission.)
Example
The following example shows how to set a default priority on port 3 to 5:
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, 6, 8, 10, 12, 14 for queues 0 - 7 respectively.
Default Setting
Weighted Round Robin
Command Mode
Global Configuration
Console(config)#interface ethernet 1/3
Console(config-if)#switchport priority default 5