Flexible NetFlow for IOS

 

If you use vpn links standart netflow don't work with vpn links. You need use flexible netflow.

It works well with vpn links. Update your IOS if your router don't support it.   

 

Example:

 

flow exporter NETFLOW1-EXPORTER

 

 description NetFlow Analyzer

 destination 172.16.0.1

 source Loopback0

 output-features

 transport udp 9996

 export-protocol netflow-v9

!

!

flow exporter NETFLOW2-EXPORTER

 description Scrutinizer

 destination 172.16.0.2

 source Loopback0

 output-features

 transport udp 9996

 export-protocol netflow-v9

!

!

flow monitor NETFLOW1

 record netflow-original

 exporter NETFLOW2-EXPORTER

 exporter NETFLOW1-EXPORTER

 cache timeout active 1

!

!

interface Tunnel12

 ip flow monitor NETFLOW1 input

 ip flow monitor NETFLOW1 output

!

!

interface FastEthernet1

 ip flow monitor NETFLOW1 input

 ip flow monitor NETFLOW1 output

 

 

link: http://www.cisco.com/en/US/prod/collateral/iosswrel/ps6537/ps6555/ps6601/ps6965/prod_white_paper0900aecd804be1cc.html