Chapter 11 QoS

The following table describes the labels in this screen.

Table 17 QoS Setting

LABEL

DESCRIPTION

Advanced

Click this link to configure QoS settings based on port number, IP address or configure

 

DSCP or ToS priority to 802.1p priority mappings.

 

 

Number of

This field displays the number of queues configurable on the switch. Click Change to edit

queues

the number of queues on the switch.

 

 

Scheduling

Select Strict Priority or Weighted Round Robin.

Method

Strict Priority scheduling singles out the highest priority queue and ensures all queued

 

traffic in this queue is transmitted before servicing the lower priority queues. Strict

 

Priority scheduling services the remaining queues using WRR.

 

Note: Queue weights can only be changed when Weighted Round

 

Robin is selected.

 

Weighted Round Robin scheduling services queues on a rotating basis based on their

 

queue weight (the number you configure in the queue Weight field). Queues with larger

 

weights get more service than queues with smaller weights.

 

 

Priority

This value indicates packet priority and is retrieved from the priority tag field of incoming

 

packets. The values range from 0 (lowest priority) to 7 (highest priority). Click the options

 

below the priority values to send packets of a specific priority to a particular queue. You

 

can also set this priority based on criteria you configure in the Advanced QoS screens.

 

See the sections later in this chapter for more information.

 

 

Queue 0 ...

This field indicates which Queue (0 to 3) you are configuring. Queue 0 has the lowest

Queue 3

priority and Queue 3 the highest priority.

 

 

Weight

You can only configure the queue weights when Weighted Round Robin is selected.

 

Bandwidth is divided across the different traffic queues according to their weights.

 

Note: If you want to use Strict Priority but want to change the weights

 

for the queues, configure them with Weighted Round Robin

 

selected first and then change the scheduling method to Strict

 

Priority.

Apply

Click Apply to save your changes to the switch.

11.3.1 Change Number of Queues

Use the Change Number of Queues screen to edit the number of queues on the switch. Click Change in the QoS Setting screen to view the following screen.

Figure 37 Change Number of Queues

Select the number of queues from the Number of Queues drop down list box and click Apply to save your settings to the switch.

 

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ES-1552 User’s Guide