Netflow config example for Cisco Catalyst version 12.1(13)E or later

mls aging long 64
mls flow ip interface-full
mls nde sender version 5 (or 9)
ip flow-export source <Interface>
ip flow-export version 5
ip flow-export destination <IP address> <port number>
interface <Interface>
   ip route-cache flow

ip flow-export source <Interface>
ip flow-export version 5
ip flow-export destination <IP address> <port number>
ip flow-cache timeout active 1 interface <Interface>
   ip route-cache flow