Say I want to monitor 2 links using netflow on a device, Ethernet4/26 and Ethernet7/17, what are their interface numbers? I'd like to use the filtering tools in the sensor settings.

Assuming I can't use SNMP to retrieve the interface numbers, how do I know what they are? Is it:

  • Interface[4/26]
  • Interface[e4/26]
  • Interface[Ethernet4/26]
  • Interface[26]
  • ?

Article Comments

Hello Incen,
thank you for your post.

Only numerical values can be used within the interface[] filter, that would be for instance:

Interface[26]



Please refer to the following article which lists the two alternatives to find the interface numbers for flow traffic:



Best Regards,


Jun, 2016 - Permalink

What does it mean if the InboundInterface number and OutboundInterface number are both 0?


Jun, 2016 - Permalink

That's not PRTG related but device-specific, other vendors are also 'suffer' with this, please review the articles below:


Jun, 2016 - Permalink