Dell PowerEdge M420 Configuration Manual page 1122

5 Set the CoS queue configuration for the (presumed) egress Gigabit
Ethernet interface 1/0/1 such that each of queues 1, 2, 3 and 4 get a
minimum guaranteed bandwidth of 25%. All queues for this interface use
weighted round robin scheduling by default. The DiffServ inbound policy
designates that these queues are to be used for the departmental traffic
through the assign-queue attribute. It is presumed that the switch will
forward this traffic to Gigabit Ethernet interface 1/0/1 based on a normal
destination address lookup for internet traffic.
console(config)#interface gigabitethernet 1/0/5
console(config-if-Gi1/0/5)#cos-queue min-
bandwidth 0 25 25 25 25 0 0
console(config-if-Gi1/0/5)#exit
console(config)#exit
1122
Configuring Differentiated Services