Dell Networking 7048 Configuration Manual page 1145

Continuing this example, the egress port te1/0/8 is configured for strict
priority on queue 6, and a weighted scheduling scheme is configured for
queues 5-0. Assuming queue 5 has a higher minimum bandwidth than queue
1 (relative bandwidth values are shown as a percentage, with 0% indicating
the bandwidth is not guaranteed), the queue service order is 6 followed by 5
followed by 1. Assuming each queue transmits all packets shown in the
diagram, the packet transmission order as seen on the network out of port
te1/0/8 is B, A, D, C. Thus, packet B, with its strict priority scheduling, is
transmitted ahead of the other packets at the egress port.
The following commands configure port 10 (ingress interface) and port 8
(egress interface).
1 Configure the Trust mode for port 10.
console#config
console(config)#interface gigabitethernet 1/0/10
console(config-if-Gi1/0/10)#classofservice trust
dot1p
2 For port 10, configure the 802.1p user priority 3 to send the packet to
queue 5 instead of the default queue (queue 3).
console(config-if-Gi1/0/10)#classofservice dot1p-
mapping 3 5
3 For port 10, specify that untagged VLAN packets should have a default
priority of 2.
console(config-if-Gi1/0/10)#vlan priority 2
console(config-if-Gi1/0/10)#exit
4 For port 8, the egress port, configure a weighted scheduling scheme for
queues 5-0.
console(config)#interface gigabitethernet 1/0/8
console(config-if-Gi1/0/8)#cos-queue min-
bandwidth 0 0 5 5 10 20 40
5 Configure port 8 to have strict priority on queue 6:
console(config-if-Gi1/0/8)#cos-queue strict 6
To configure the CoS queues for lossless traffic when transporting iSCSI
traffic, set the lossless traffic class to have a one-to-one mapping with the
priority value. The following example illustrates how to change the dot1p
mapping from the switch defaults to support lossless transport of frames on
Configuring Class-of-Service
1145