Problem

NetVizura charts are showing lower NetFlow traffic than expected. Here are several reasons why this might happen:

  1. Trial license limitation
  2. Network device misconfiguration
  3. Flow Sampling
  4. Interface congestion

Solution

  1. Trial license limitation

    If you have a trial license, you should be aware that it has limitation, currently set to 500 flows/s. If your network device sends more than 500 flows/s, you will be able to see only 500 flows/s, while the rest will be dropped. You can check the number of received and dropped flows in the System Data (NFA). If you see dropped flows, send email to support@netvizura.com with the screenshot of the System tab, so that we can help further.

  2. Network device misconfiguration

    If you did not properly configure your network device, your NetFlow charts will not show correct data. The most common reason for this is if you did not enable NetFlow (Ingress) on all active interfaces (Ingress vs. Egress).

  3. Flow Sampling

    If you are using NetFlow flow sampling on your network device, your data shown in NetVizura charts will be lower. NetVizura has an option to multiply received data (Bytes, Packets, Flows) as much as needed to get a more realistic traffic in the charts (Sampling Settings).    

     

  4. Interface congestion


    In some cases, the reason for showing lower NetFlow data can be in overloaded interface, especially if you are using the same interface for other network traffic along with the NetFlow. It would be the best if you could use your server only for the NetFlow traffic.

 

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