Example Class Map Configuration

This example shows a traffic class configured with the class-map match-all command:

Router(config)# class-map match-all ciscol Router(config-cmap)# match protocol ip Router(config-cmap)# match qos-group 4 Router(config-cmap)# match access-group 101

If a packet arrives on a router with traffic class called cisco1 configured on the interface, the packet is evaluated to determine if it matches the IP protocol, QoS group 4, and access group 101. If all three of these match criteria are met, the packet matches traffic class cisco1.

You can use match commands to specify various criteria for classifying packets. Packets are checked to determine whether they match the criteria specified in the match commands. If a packet matches the specified criteria, that packet is considered a member of the class and is forwarded according to the QoS specifications set in the traffic policy. Packets that fail to meet any of the matching criteria are classified as members of the default traffic class. The MQC does not necessarily require that you associate a single traffic class to one traffic policy. You can associate multiple types of traffic with a single traffic class by using the match any command.

The match not command inverts the condition specified. This command specifies a match criterion value that prevents packets from being classified as members of a specified traffic class. All other values of that particular match criterion belong to the class.

The MQC allows multiple traffic classes (nested traffic classes, which are also called nested class maps) to be configured as a single traffic class. This nesting can be achieved with the use of the match class-map command. The only method of combining match-any and match-all characteristics within a single traffic class is with the match class-map command.

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