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What is the interface number?



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]
  • ?

interface netflow-sensor number

Created on Jun 8, 2016 9:05:08 PM

Last change on Jun 9, 2016 5:59:02 AM by  Luciano Lingnau [Paessler]

3 Replies



Hello Incen,
thank you for your post.

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


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

Best Regards,

Created on Jun 9, 2016 9:20:47 AM by  Luciano Lingnau [Paessler]

Last change on Jun 9, 2016 9:21:45 AM by  Luciano Lingnau [Paessler]



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

Created on Jun 9, 2016 6:00:54 PM



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

Created on Jun 10, 2016 11:46:32 AM by  Luciano Lingnau [Paessler]

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