Dell PowerConnect 8100 CLI Reference Guide - Page 650

User Guidelines The maximum number of queues supported per interface is seven. It is recommended that the operator avoid the use of queue 5-7 in order to avoid conflicts with inter- and intra-network control traffic. In order to better accommodate bursty traffic, it is recommended that the sum of the configured min-bandwidths be much less than 100%. Configuring the minimum bandwidths such that they sum to 100% effectively locks the scheduler such that bandwidth sharing by lower priority queues cannot be accommodated under congestion conditions. When ETS is operational on a switch, this command overrides the ETS assignments and assigns minimum bandwidth constraints across traffic class groups. This allows the administrator to ensure that the frame scheduler does not completely starve lower priority groups when strict priority is enabled on a high numbered TCG. Specifically, assigning a minimum bandwidth to a lower numbered TCG, even when strict priority is enabled on a higher numbered TCG, will alter the normal scheduler behavior and cause the scheduler to process frames from the lower numbered TCG to conform to the min-bandwidth constraint. Example The following example displays how to specify the minimum transmission bandwidth guarantee for cos-queues 0 through 6. console(config)#cos-queue min-bandwidth 5 5 10 10 0 0 0 cos-queue random-detect Use the cos-queue random-detect command in Global Configuration or Interface Configuration mode to enable WRED queue management policy on an interface CoS queue. Use the no form of the command to disable WRED policy for a CoS queue on an interface. Syntax cos-queue {random-detect queue-id1 [queue-id2..queue-idn]} no cos-queue {random-detect queue-id1 [queue-id2..queue-idn]} 650 QoS Commands