Alcatel-Lucent 6850-48 网络指南

Configuring Global QoS Parameters

Configuring QoS

page 40-14

OmniSwitch AOS Release 6 Network Configuration Guide

This section describes the global QoS configuration, which includes enabling and disabling QoS, applying 
and activating the configuration, controlling the QoS log display, and configuring QoS port and queue 
parameters.

By default QoS is enabled on the switch. If QoS policies are configured and applied, the switch will 
attempt to classify traffic and apply relevant policy actions.

To disable the QoS, use the 

 command. For example:

-> qos disable

QoS is immediately disabled. When QoS is disabled globally, any flows coming into the switch are not 
classified (matched to policies). 

To re-enable QoS, enter the qos command with the enable option:

-> qos enable

QoS is immediately re-enabled. Any policies that are active on the switch will be used to classify traffic 
coming into the switch.

Note that individual policy rules may be enabled or disabled with the 

 command. 

By default, bridged, routed, and multicast flows that do not match any policies are accepted on the switch. 
To change the global default disposition (which determines whether the switch will accept, deny, or drop 
the flow), use the desired disposition setting (accept, drop, or deny) with any of the following commands: 

, or 

. 

In the current release, the drop and deny options produce the same result (flows are silently dropped; no 
ICMP message is sent).

For example, to deny any routed flows that do not match policies, enter:

-> qos default routed disposition deny

To activate the setting, enter the qos apply command. For more information about the qos apply 
command, see 

.

Typically, the disposition is only configured when you are using policies for Access Control Lists (ACLs). 

Note that if you set qos default bridged disposition to deny, you effectively drop all Layer 2 traffic that 
does not match any policy. If you want to create ACLs to allow some Layer 2 traffic through the switch, 
you must configure two rules for each type of Layer 2 traffic, one for source and one for destination. For 
more information about ACLs, see