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Catalyst 3560 Switch Software Configuration Guide
OL-8553-06
Chapter 34 Configuring QoS
Configuring Standard QoS
Switch(config-ext-mac)# exit
Switch(config)# class-map macclass1
Switch(config-cmap)# match access-group maclist1
Switch(config-cmap)# exit
Switch(config)# policy-map macpolicy1
Switch(config-pmap)# class macclass1
Switch(config-pmap-c)# set dscp 63
Switch(config-pmap-c)# exit
Switch(config-pmap)# class macclass2 maclist2
Switch(config-pmap-c)# set dscp 45
Switch(config-pmap-c)# exit
Switch(config-pmap)# exit
Switch(config)# interface gigabitethernet0/1
Switch(config-if)# mls qos trust cos
Switch(config-if)# service-policy input macpolicy1
Classifying, Policing, and Marking Traffic on SVIs by Using Hierarchical Policy Maps
In Cisco IOS Release 12.2(25)SE or later, you can configure hierarchical policy maps on SVIs, but not
on other types of interfaces. Hierarchical policing combines the VLAN- and interface-level policy maps
to create a single policy map.
On an SVI, the VLAN-level policy map specifies which traffic class to act on. Actions can include
trusting the CoS, DSCP, or IP precedence values or setting a specific DSCP or IP precedence value in
the traffic class. Use the interface-level policy map to specify the physical ports that are affected by
individual policers.
Follow these guidelines when configuring hierarchical policy maps:
Before configuring a hierarchical policy map, you must enable VLAN-based QoS on the physical
ports that are to be specified at the interface level of the policy map.
You can attach only one policy map per ingress port or SVI.
A policy map can contain multiple class statements, each with different match criteria and actions.
A separate policy-map class can exist for each type of traffic received on the SVI.
Beginning with Cisco IOS Release 12.2(40)SE, a policy-map and a port trust state can both run on
a physical interface. The policy-map is applied before the port trust state.
If you configure the IP-precedence-to-DSCP map by using the mls qos map ip-prec-dscp
dscp1...dscp8 global configuration command, the settings only affect packets on ingress interfaces
that are configured to trust the IP precedence value. In a policy map, if you set the packet IP
precedence value to a new value by using the set ip precedence new-precedence policy-map class
configuration command, the egress DSCP value is not affected by the IP-precedence-to-DSCP map.
If you want the egress DSCP value to be different than the ingress value, use the set dscp new-dscp
policy-map class configuration command.
In Cisco IOS Release 12.2(25)SE or later, if you enter or have used the set ip dscp command, the
switch changes this command to set dscp in its configuration. If you enter the set ip dscp command,
this setting appears as set dscp in the switch configuration.
In Cisco IOS Release 12.2(25)SEC or later, you can use the set ip precedence or the set precedence
policy-map class configuration command to change the packet IP precedence value. This setting
appears as set ip precedence in the switch configuration.
If VLAN-based QoS is enabled, the hierarchical policy map supersedes the previously configured
port-based policy map.