Cisco Cisco IOS Software Release 12.2(14)S

This document describes the NetFlow Subinterface Support feature and includes the following sections:

The NetFlow Subinterface Support feature provides the ability to enable NetFlow on a per-subinterface 
basis. In a scenario in which your network contains thousands of subinterfaces and you want to collect 
export records from only a few subinterfaces, you can fine-tune your collection of data to only specified 
subinterfaces. The result is lower bandwidth requirements for NetFlow Data Export (NDE) and reduced 
platform requirements for NetFlow data-collection devices.

Using the NetFlow Subinterface Support feature, you can enable NetFlow on selected subinterfaces 
using the ip flow ingress command. If you configure the ip flow ingress command on a few selected 
subinterfaces and then configure the ip route-cache flow command on the main interface, enabling the 
main interface will overwrite the ip flow ingress command and data collection will start from the main 
interface as well as all the subinterfaces. In a scenario in which you configure the ip flow ingress 
command and then configure the ip route-cache flow command on the main interface, you can restore 
subinterface data collection by using the no ip route-cache flow command. This configuration will 
disable data collection from the main interface and restore data collection to the subinterfaces you 
originally configured with the ip flow ingress command.

12.2(14)S

This feature was introduced.

12.2(15)T

This feature was integrated into Cisco IOS Release 12.2 T.