Use either the showclass-map command or the showpolicy-mapinterface command to verify the setting of the Layer 3 packet length value used as a match criterion for the class map and the policy map. The following section begins with sample output of the showclass-mapcommand and concludes with sample output of the showpolicy-mapinterface command.
The sample output of the showclass-map command shows the defined class map and the specified match criterion. In the following example, a class map called "class1" is defined. The Layer 3 packet length has been specified as a match criterion for the class. Packets with a Layer 3 length of between 100 bytes and 300 bytes belong to class1.
Router# show class-map
class-map match-all class1
match packet length min 100 max 300
The sample output of the showpolicy-mapinterface command displays the statistics for FastEthernet interface 4/1/1, to which a service policy called "mypolicy" is attached. The configuration for the policy map called "mypolicy" is given below.
Router(config)# policy-map mypolicy
Router(config-pmap)# class class1
Router(config-pmap-c)# set qos-group 20
Router(config)# interface fastethernet4/1/1
Router(config-if)# service-policy input mypolicy
The following are the statistics for the policy map called "mypolicy" attached to FastEthernet interface 4/1/1. These statistics confirm that matching on the Layer 3 packet length has been configured as a match criterion.
Router# show policy-map interface
Service-policy input: mypolicy
Class-map: class1 (match-all)
500 packets, 125000 bytes
5 minute offered rate 4000 bps, drop rate 0 bps
Match: packet length min 100 max 300
Packets marked 500