Cannot get FastEthernet QoS working on 3550

I need to lock down the bandwidth awailable to one port of a 3550. I understand the bandwidth command is present but non functional on the

I'm trying to use 8000 bits per second to test and then increase the bandwidth once I've proved the configuration is working.

None of the outputs below register any packets hitting the policy.

Any help appreciated

mls qos

interface FastEthernet0/21 switchport access vlan 251 switchport mode access no ip address service-policy output 4contractors spanning-tree portfast

policy-map 4contractors class class-default police 8000 8000 exceed-action drop

Router#sh policy-map in fas 0/21

FastEthernet0/21

service-policy output: 4contractors

class-map: class-default (match-any) 0 packets, 0 bytes 5 minute offered rate 0 bps, drop rate 0 bps match: any 0 packets, 0 bytes 5 minute rate 0 bpsqm_police_inform_feature: CLASS_SHOW

Router#sh mls qos in fas 0/21 FastEthernet0/21 trust state: not trusted COS override: dis Attached policy-map for Egress: 4contractors default COS: 0 DSCP Mutation Map: Default DSCP Mutation Map

Router#sh class Class Map match-any class-default (id 0) Match any

sh policy-map in fas 0/21 sh mls qos in fas 0/21