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Catalyst 3550 Multilayer Switch Software Configuration Guide
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Chapter 20 Configuring QoS
Configuring QoS
To return a port to its non-trusted state, use the no mls qos trust interface configuration command. To
return to the default DSCP-to-DSCP-mutation map values, use the no mls qos map dscp-mutation
dscp-mutation-map-name global configuration command.
This example shows how to configure Gigabit Ethernet port 0/2 to the DSCP-trusted state and to modify
the DSCP-to-DSCP-mutation map (named gi0/2-mutation) so that incoming DSCP values 10 to 13 are
mapped to DSCP values 30 to 33:
Switch# configure terminal
Switch(config)# mls qos map dscp-mutation gi0/2-mutation 10 11 12 13 to 30 31 32 33
Switch(config)# interface gigabitethernet0/2
Switch(config-if)# mls qos trust dscp
Switch(config-if)# mls qos dscp-mutation gi0/2-mutation
Switch(config-if)# end
Configuring a QoS Policy
Configuring a QoS policy typically requires classifying traffic into classes, configuring policies applied
to those traffic classes, and attaching policies to interfaces.
For background information, see the
“Classification” section on page 20-4
and the
“Policing and
Marking” section on page 20-8
.
This section contains this configuration information:
•
Classifying Traffic by Using ACLs, page 20-27
•
Classifying Traffic by Using Class Maps, page 20-30
•
Classifying, Policing, and Marking Traffic by Using Policy Maps, page 20-32
•
Classifying, Policing, and Marking Traffic by Using Aggregate Policers, page 20-37
Step 6
mls qos dscp-mutation
dscp-mutation-name
Apply the map to the specified ingress DSCP-trusted port.
You can apply the map to different Gigabit-capable Ethernet ports.
However, on 10/100 Ethernet ports, you can attach only one
DSCP-to-DSCP-mutation map to a group of twelve ports. For example,
Fast Ethernet ports 0/1 to 0/12 are a group, Fast Ethernet ports 0/13 to
0/24 are a group, Gigabit Ethernet 0/1 is a group, and Gigabit Ethernet
0/2 is a group. When applying a mutation map to any port in a group,
all ports in the same group are automatically configured with the same
map.
Step 7
end
Return to privileged EXEC mode.
Step 8
show mls qos maps dscp-mutation
Verify your entries.
Step 9
copy running-config startup-config
(Optional) Save your entries in the configuration file.
Command
Purpose
