What is this?

This knowledgebase contains questions and answers about PRTG Network Monitor and network monitoring in general.

Learn more

PRTG Network Monitor

Intuitive to Use. Easy to manage.
More than 500,000 users rely on Paessler PRTG every day. Find out how you can reduce cost, increase QoS and ease planning, as well.

Free Download

Top Tags

View all Tags

Comparing Netflow data to SNMP Interface data



I have Netflow enabled on an interface like so:

Interface f0/0/1 ip flow ingress ip flow egress

Then I have two separate sensors on PRTG filtering Netflow data going in and out of the interface using this filter for the inbound traffic: InboundInterface[1]

And for the outbound traffic: OutboundInterface[1]

I'm also monitoring the same interface using SNMP, which gives me the standard three channels: Traffic Total, Traffic IN, Traffic OUT.

The problem is, when I compare my SNMP data to my netflow data for the outbound or inbound traffic, they don't match up!

Netflow shows more total traffic than SNMP.

Why could this be?

cisco netflow-v9 snmp

Created on Apr 19, 2015 9:39:21 PM

2 Replies



Dear JP Escobari

In which magnitude are you seeing more Netflow traffic than SNMP traffic? For example, some percent more? Twice or ten time as much?

Created on Apr 21, 2015 12:16:59 PM by  Arne Seifert [Paessler Support]

Last change on Apr 21, 2015 12:17:21 PM by  Arne Seifert [Paessler Support]



False alarm Dear Arne!

I was getting duplicate Netflow data probably because that device is a branch router and I had both IP Egress and IP Ingress configured on the interface.

Now I'm only using IP Ingress on the interface and still getting the OUT data that I needed to monitor.

I can verify the problem is solved because my Netflow OUT data graph resembles the SNMP Traffic OUT graph.

Thanks for your kind support! You guys are the best.


Juan Pablo Escobari

Created on Apr 21, 2015 4:08:53 PM

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.