33-1

C
HAPTER
33
C
LASS
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ERVICE
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OMMANDS
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 eight 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 mappi ng of
frame priority tags to the switch’s priority queues.

Priority Commands (Layer 2)

This section describes commands used to configure Layer 2 traffic priority
on the switch.
Table 33-1 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
33-1
Priority (Layer 3 and 4) Maps TCP ports, IP precedence tags, or IP
DSCP tags to class of service values
33-11
Table 33-2 Priority Commands (Layer 2)
Command Function Mode Page
Global Priority Settings
priority bits Sets priority bits in the VLAN tag of
packets sent by the CPU
GC 33-2
queue mode Sets the queue mode to strict priority,
Weighted Round-Robin (WRR), or hybrid
GC 33-3