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Cisco ME 3400 EthernetAccess Switch SoftwareConfiguration Guide
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Chapter30 Configuring QoS Configuring QoS
Attaching a Traffic Policy to an Interface
You use the service-policy interface configuration command to at tach a traf f ic polic y to a n interf ace and
to specify the direction in which the policy should be applied: either an input policy map for incoming
traffic or an output policy map for outgoing traffic. Input and output policy maps support different QoS
features. See the “Configuring Input Policy Maps” section on page 30-35 and the “Configuring Output
Policy Maps” section on page 30-43 for restrictions on input and output policy maps.
You can attach a service policy only to a physical port. You can attach only one input policy map and
one output policy map per port.
Beginning in privileged EXEC mode, follow these steps to attach a policy map to a port:
To remove the policy map and port association, use the no service-policy {input | output}
policy-map-name interface configuration command.
Configuring Input Policy Maps
Policy maps specify which traffic class to act on and what actions to take. All traffic that fails to meet
matching criteria of a traffic class belongs to the default class. Input policy maps regulate traffic entering
the switch. In an input policy, you can match CoS, DSCP, IP precedence, or ACLs, and configure
individual policing, aggregate policing, or marking to a CoS, DSCP, IP precedence, or QoS group value.
Follow these guidelines when configuring input policy maps:
You can attach only one input policy map per port.
The maximum number of policy maps configured on the switch is 256.
The maximum number of classes in each input policy map is 32.
The number of input policy maps that can be attached in a switch is limited by the availability of
hardware resources. If you attempt to attach an input policy map that ca uses any hardware resource
limitation to be exceeded, the configuration fails.
After you have attached an input policy map to an interface by using the service-policy input
interface configuration command, you can modify the policy without detaching it from the interface.
You can add or delete classification criteria, add or delete classes, add or delete actions, or change
the parameters of the configured actions (policers, rates, mapping, marking, and so on).
You cannot configure hierarchical policy maps as input policy maps.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface interface-id Specify the port to attach to the policy map, and enter interface
configuration mode. Valid interfaces are physical ports.
Step3 service-policy {input | output}
policy-map-name Specify the policy-map name and whether it is an input policy
map or an output policy map.
Step4 end Return to privileged EXEC mode.
Step5 show policy-map interface [interface-id] Verify your entries.
Step6 copy running-config startup-config (Optional) Save your entries in the configuration file.