H3C S9500 Series Operation Manual

Also see for S9500 Series: Operation manual Operation manual Operation manual Operation manual Operating manual

Contents

Operation Manual – QoS/ACLH3C S9500 Series Routing Switches Chapter 2 QoS Configuration2-18Table 2-13 Configure queue schedulingOperation CommandConfiguring queueschedulingqueue-scheduler wrr { group1 { queue-idqueue-weight } &<1-8> | group2 { queue-idqueue-weight } &<1-8> }*Restore the default setting undo queue-scheduler [ queue-id ] &<1-8>By default, the switch uses all-SP mode, so those queues not configured with WRRalgorithm are SP mode.See the corresponding Command Manual for details of the commands.2.2.7 Configuring WRED ParametersIn the case of network congestion, the switch drops packets to release systemresources. And then no packets are put into long-delay queues.The switch allocates drop precedence for it when receiving a packet (also calledcoloring the packet). The drop precedence values range from 0 to 2, with 2 for red, 1 foryellow and 0 for green. In congestion, red packets will be first dropped, and greenpackets last.You can configure drop parameters and thresholds by queue or drop precedence.The following two drop modes are available:1) Tail drop mode: Different queues (red, yellow and red) are allocated with differentdrop thresholds. When these thresholds are exceeded respectively, excessivepackets will be dropped.2) WRED drop mode: Drop precedence is taken into account in drop action. Whenonly min-thresholds of red, yellow and green packets are exceeded, excessivepackets are dropped randomly at given probability. But when max-thresholds ofred, yellow and green packets are exceeded, all excessive packets will bedropped.You must first configure WRED parameters for every outbound queue in defining dropprecedence.I. Configuring WRED parametersThe switch provides four sets of default WRED parameters, respectively numbered as0 to 3. Each set includes 80 parameters, 10 parameters for each of the eight queues.The ten parameters are green-min-threshold, yellow-min-threshold, red-min-threshold,green-max-threshold, yellow-max-threshold, red-max-threshold, green-max-prob,yellow-max-prob, red-max-prob and exponent. Red, yellow and green packetsrespectively refer to those with drop precedence levels 2, 1 and 0.You can use the following commands to configure WRED parameters.