SMC Networks 6152PL2 FICHE, Management Manual

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Class of Service Commands
4-363
4
Class of Service Commands
The commands described in this section allow you to specify which data packets
have greater precedence when traffic is buffered in the switch due to congestion.
This switch supports CoS with four priority queues for each port. Data packets in a
port’s high-priority queue will be transmitted before those in the lower-priority
queues. You can set the default priority for each interface, the relative weight of each
queue, and the mapping of frame priority tags to the switch’s priority queues.
Priority Commands (Layer 2)
This section describes the commands used to configure Layer 2 traffic priority on the
switch.
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.
Table 4-87 Priority Commands
Command Groups Function Page
Priority (Layer 2) Configures default priority for untagged frames, sets queue weights,
and maps class of service tags to hardware queues
4-363
Priority (Layer 3 and 4) Maps IP DSCP tags to class of service values 4-368
Table 4-88 Priority Commands (Layer 2)
Command Function Mode Page
queue mode Sets the queue mode to strict priority or Weighted
Round-Robin (WRR)
GC 4-363
switchport priority default Sets a port priority for incoming untagged frames IC 4-364
queue cos map Assigns class-of-service values to the priority queues IC 4-365
show queue mode Shows the current queue mode PE 4-366
show queue bandwidth Shows round-robin weights assigned to the priority queues PE 4-366
show queue cos-map Shows the class-of-service map PE 4-367
show interfaces switchport Displays the administrative and operational status of an
interface
PE 4-232