Chapter 19: QoS Configuration Guide
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DIGITAL GIGAswitch/Router User Reference Manual
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 trunk
ports, the frame is assigned an 802.1Q priority. Select a number from 0 to 7. The
mapping of 802.1Q to internal priorities is the following: (0 = low) (1,2,3 =medium)
(4,5,6 = high) (7 = control).
To set a QoS policy on a layer-2 flow, enter the following command in Configure mode:
Traffic Prioritization for Layer-3 & Layer-4 Flows
QoS policies applied at layer-3 and 4 allow you to assign priorities based on specific fields
in the IP and IPX headers. You can set QoS policies for IP flows based on source IP
address, destination IP address, source TCP/UDP port, destination TCP/UDP port, type
of service (TOS) and transport protocol (TCP or UCP). You can set QoS policies for IPX
flows based on source network, source node, destination network, destination node,
source port and destination port. A QoS policy set on an IP or IPX flow allows you to
classify the priority of traffic based on:
•
Layer-3 source-destination flows
•
Layer-4 source-destination flows
•
Layer-4 application flows
Configuring IP QoS Policies
To configure an IP QoS policy, perform the following tasks:
1.
Identify the Layer-3 or 4 flow and set the IP QoS policy.
2.
Specify the precedence for the fields within an IP flow.
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
control|high|medium|low|
<trunk-priority>
