Cisco IE 4000, Software Configuration Manual

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Configuring QoS
Configuring QoS
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, ACLs, or VLAN IDs 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 total number of configurable policer profiles on the switch is 256; the total number of supported policer
instances on the switch is 1024 minus one more than the total number of interfaces on the switch. On a 24-port
switch, the number of available policer instances is 999. You can use a policer profile in multiple instances.

The maximum number of classes in each input policy map is 64 plus class-default .

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 causes any hardware resource limitation to be exceeded, the
configuration fails.

After you have attached a single-level 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). This also applies to changing criteria for the child policy of a
hierarchical policy map, as in a per-port per-VLAN hierarchical policy map.
For the parent policy of a hierarchical policy map, you cannot add or delete a class at the parent level if the policy
map is attached to an interface. You must detach the policy from the interface, modify the policy, and then re-attach
it to the interface.

You can configure a maximum 2-level hierarchical policy map as an input policy map only with VLAN-based
classification at the parent level and no VLAN-based classification at the child level.

When an input policy map with only Layer 2 classification is attached to a routed port or a switch port containing a
routed SVI, the service policy acts only on switching eligible traffic and not on routing eligible traffic.
Command Purpose
1. configure terminal Enter global configuration mode.
2. interface interface-id Specify the port to attach to the policy map, and enter interface
configuration mode. Valid interfaces are physical ports.
3. 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.
4. end Return to privileged EXEC mode.
5. show policy-map interface [ interface-id ] Verify your entries.
6. copy running-config startup-config (Optional) Save your entries in the configuration file.