Chapter 31
Configuring QoS
Enabling QoS Globally
By default, QoS is disabled on the switch.
Beginning in privileged EXEC mode, follow these steps to enable QoS. This procedure is required.
Command
Step 1
configure terminal
Step 2
mls qos
Step 3
end
Step 4
show mls qos
Step 5
copy running-config startup-config
To disable QoS, use the no mls qos global configuration command.
Configuring Classification Using Port Trust States
These sections describe how to classify incoming traffic by using port trust states. Depending on your
network configuration, you must perform one or more of these tasks.
•
•
•
Configuring the Trust State on Ports within the QoS Domain
Packets entering a QoS domain are classified at the edge of the QoS domain. When the packets are
classified at the edge, the switch port within the QoS domain can be configured to one of the trusted
states because there is no need to classify the packets at every switch within the QoS domain.
shows a sample network topology.
OL-23389-01
Purpose
Enter global configuration mode.
Enable QoS globally.
QoS runs with the default settings described in the
Configuration" section on page
section on page
page
Return to privileged EXEC mode.
Verify your entries.
(Optional) Save your entries in the configuration file.
Configuring the Trust State on Ports within the QoS Domain, page 31-9
Configuring the CoS Value for an Interface, page 31-11
Enabling DSCP Transparency Mode, page 31-11
31-4, and the
"Queueing on Egress Queues" section on
31-5.
Catalyst 2928 Switch Software Configuration Guide
Configuring Standard QoS
"Default Standard QoS
31-7, the
"Queueing on Ingress Queues"
Figure 31-6
31-9