DES-1228/ME Metro Ethernet Managed Switch CLI Reference Guide
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OMMANDS
The Switch supports 802.1p priority queuing. The Switch has four priority queues. These priority queues are numbered from 3
(Class 3) — 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 Q1 queue.
Priority 1 is assigned to the Switch’s Q0 queue.
Priority 2 is assigned to the Switch’s Q0 queue.
Priority 3 is assigned to the Switch’s Q1 queue.
Priority 4 is assigned to the Switch’s Q2 queue.
Priority 5 is assigned to the Switch’s Q2 queue.
Priority 6 is assigned to the Switch’s Q3 queue.
Priority 7 is assigned to the Switch’s Q3 queue.
Priority scheduling is implemented by the priority queues stated above. The Switch will empty the four hardware priority queues
in order, beginning with the highest priority queue, 3, 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.
The QoS commands in the Command Line Interface (CLI) are listed (along with the appropriate parameters) in the following
table:
Command
Parameters
config bandwidth_control
[<portlist>] {rx_rate [no_limit | <value 64-1024000>] | tx_rate [no_limit
<value 64-1024000>]} (1)
show bandwidth_control
{<portlist>}
config scheduling
<class_id 0-3> [strict | weight <value 1-55>]
config scheduling_mechanism
[strict | weight_fair]
show scheduling
show scheduling_mechanism
config 802.1p user_priority
<priority 0-7> <class_id 0-3>
show 802.1p user_priority
config 802.1p default_priority
[<portlist> | all] <priority 0-7>
show 802.1p default_priority
<portlist>
config cos mapping ports
[<portlist> | all] [none | {ethernet [802.1p ] | ip [tos | dscp] } (1) ]
show cos mapping
{port <portlist> }
config cos tos value
<value 0-7> [class <class_id 0-3>]
show cos tos
{value <value 0-7>}
config dscp_mapping
dscp_value <value 0-63> [class <class_id 0-3>]
show dscp_mapping
{dscp_value <value 0-63> }
Each command is listed, in detail, in the following sections:
