Cabletron Systems 9032578-05 manual Configuring Layer-2 QoS, 802.1p Priority Mapping, Control

Chapter 21: QoS Configuration Guide

If a port operates in flow-bridging mode, you can be more specific and configure priorities for frames that match both a source AND a destination MAC address and a VLAN ID. You can also specify a list of ports to apply the policy.

The VLAN ID in the QoS configuration must match the VLAN ID assigned to the list of ports to which the QoS policy is applied. In a layer-2 only configuration, each port has only one VLAN ID associated with it and the QoS policy should have the same VLAN ID. When different VLANs are assigned to the same port using different protocol VLANs, the layer-2 QoS policy must match the VLAN ID of the protocol VLAN.

Note: In flow mode, you can also ignore the source MAC address and configure the priority based on the destination MAC address only.

Configuring Layer-2 QoS

When applying QoS to a layer-2 flow, priority can be assigned as follows:

•The frame gets assigned a priority within the switch. Select “low, medium, high or control.”

•The frame gets assigned a priority within the switch, AND if the exit ports are VLAN trunk ports, the frame is assigned an 802.1Q priority. Select a number from 0 to 7.

To set a QoS priority on a layer-2 flow, enter the following command in Configure mode:

Set a Layer-2 QoS policy.

qos set l2 name <name> source-mac <MACaddr> dest-mac <MACaddr> vlan <vlanID> in-port-list <port-list>priority controlhighmediumlow<trunk-priority>

802.1p Priority Mapping

The following table shows the default mapping of 802.1p class of service (CoS) values to internal priorities for frames that are received on a port on the SSR:

Table 9: Default Priority Map

802.1p CoS	Internal Priority
Values	Queue
1, 2	Low
0, 3	Medium
4, 5	High
6, 7	Control

294 SmartSwitch Router User Reference Manual