xStack
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DGS-3600 Series Layer 3 Gigabit Ethernet Managed Switch CLI Manual
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QUALITY OF SERVICE (QOS) COMMANDS
The Switch supports 802.1p priority queuing. The Switch has seven configurable priority queues. These priority queues
are numbered from 6 (Class 6) — the highest priority queue — to 0 (Class 0) — the lowest priority queue. The eight
priority tags specified in IEEE 802.1p (p0 to p7) are mapped to the Switch’s priority queues as follows:
• Priority 0 is assigned to the Switch’s Q2 queue.
• Priority 1 is assigned to the Switch’s Q0 queue.
• Priority 2 is assigned to the Switch’s Q1 queue.
• Priority 3 is assigned to the Switch’s Q3 queue.
• Priority 4 is assigned to the Switch’s Q4 queue.
• Priority 5 is assigned to the Switch’s Q5 queue.
• Priority 6 is assigned to the Switch’s Q6 queue.
• Priority 7 is assigned to the Switch’s Q6 queue.
Priority scheduling is implemented by the priority queues stated above. The Switch will empty the eight hardware priority
queues in order, beginning with the highest priority queue, 6, to the lowest priority queue, 0. Each hardware queue will
transmit all of the packets in its buffer before permitting the next lower priority to transmit its packets. When the lowest
hardware priority queue has finished transmitting all of its packets, the highest hardware priority queue will begin
transmitting any packets it may have received.
NOTICE: The Switch contains eight classes of service for each port on the Switch. One of these
classes is reserved for internal use on the Switch and therefore is not configurable. All references in
the following section regarding classes of service will refer to only the seven classes of service that
may be used and configured by the Switch’s Administrator.
The Quality of Service (QoS) commands in the Command Line Interface (CLI) are listed (along with the appropriate
parameters) in the following table.
