Dell PowerConnect 55xx Systems User Guide 657FILE LOCATION: C:\Users\gina\Desktop\Checkout_new\Maintenance Projects\DellContax\sources\CxUGQoS.fmD E L L C O N F I D E N T I A L – P R E L I M I N A R Y 1 0 / 3 0 / 1 3 - F O R P R O O F O N LYConfiguring QoS Properties Using CLI CommandsThe following table summarizes the CLI commands for configuring fields inthe QoS Properties: Summary page.The following is an example of the CLI command:QueueThe switch supports eight queues for each interface. Queue number eight isthe highest priority queue. Queue number one is the lowest priority queue.Traffic Limitation MethodsThere are two ways of determining how traffic in queues is handled, StrictPriority and Weighted Round Robin (WRR):• Strict Priority — Egress traffic from the highest-priority queue istransmitted first. Traffic from the lower queues is processed only after thehighest queue has been transmitted, thus providing the highest level ofpriority of traffic to the lowest-numbered queue.• Weighted Round Robin (WRR) — In WRR mode, the number of packetssent from the queue is proportional to the weight of the queue (the higherthe weight, the more frames are sent). For example, if all eight queues areWRR and the default weights are used, queue 1 receives 1/15 of thebandwidth (assuming all queues are saturated and there is congestion),queue 2 receives 2/15, queue 3 receives 4/15, and queue 8 receives 8/15 ofthe bandwidth. The type of WRR algorithm used in the device is not thestandard Deficit WRR (DWRR), but rather Shaped Deficit WRR(SDWRR).Table 22-2. QoS Properties CLI CommandsCLI Command Descriptionqos cos default-cosno qos cosDefines the default CoS value of a port.Use the no form of this command to restore thedefault configuration.console(config)# interface gi1/0/15console(config-if)# qos cos 3
