For DSCP, all values are assigned to the
normal
queue, with
normal
priority, by default.
7.6.9.2 SET
Configures the Quality of Service global parameters.
Syntax:
ethernet
X/X
switch config>qos set
queue
Priority queue
priority
Scheduling discipline for the switch egress queues
7.6.9.2.1 SET QUEUE
Configures the weighted table the scheduler is going to use in each output queue for a port, when said port is con-
figured in Weighted Round Robin mode.
The weighted tables define the relative priority of one queue compared to another. The weight assigned to each
queue establishes how many times the scheduler checks for the presence of packets in said queue, for each of the
scheduler’s cycles.
In each check, if a packet is found in the queue, it is transmitted (provided the output rate control allows this). In prac-
tice, when faced with congestion, the scheduler assumes the output rate is shared in the following proportions: 53%
(8/15), 27% (4/15), 13% (2/15), 7% (1/15).
Syntax:
ethernet
X/X
switch config>qos set queue <queue> weight <value>
queue:
Queue you want to configure. Possible values are:
urgent
,
high
,
normal
and
low
.
value:
Weight value to assign to the queue. This ranges from <1..100> or <1..49> de-
pending on the switch. The sum of the weights can be below or above the 100
value, as the relative weight for each queue is equal to the value configured, di-
vided by the sum of the weights for the four queues.
Example:
Sets a weighted table for the 60-30-9-1 Urgent-High-Normal-Low queues.
ethernet0/0 switch config>qos set queue low weight 1
ethernet0/0 switch config>qos set queue normal weight 9
ethernet0/0 switch config>qos set queue high weight 30
ethernet0/0 switch config>qos set queue urgent weight 60
ethernet0/0 switch config>
7.6.9.2.2 SET PRIORITY
Sets service priorities for outgoing switch queues.
Syntax:
ethernet
X/X
switch config>qos set priority <strict|urgent-strict|wrr>
• Priority can take the following values:
•
strict
: The queues are served with strict priority. This means that packets are not transmitted when there are pack-
ets in higher priority queues awaiting transmission (i.e., packets in the
low
queue are not transmitted if packets in
the other three queues are awaiting transmission). One needs to be careful with this priority, as it can lead to some
queues never transmitting anything.
•
urgent
-
strict
: The
urgent
queue transmits with a strict priority and the other three queues with Weighted Round
Robin priority. This means that packets from the other queues are not transmitted if there are packets in the urgent
queue. This priority must also be used carefully, as it can lead to situations where only packets from the urgent
queue are transmitted.
•
wrr
: All queues are transmitted in accordance with the Weighted Round Robin system. This means they are trans-
mitted in a cycle, according to a weighted table that determines how many times polling is planned for each queue
in each cycle. This is the default mode for the switch feature.
7.6.10 STORM-CONTROL
Configures the global parameters for traffic storm control.
Teldat SA
7 Switch Configuration
LAN Interfaces
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