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

How does a netflow include filter impact probe/server performance when channel definitions are IP on



We have a custom Netflow sensor that we use to collect 95% Mbps data by IP for client billing (we're a public web host). Each client has two channels assigned, data in and data out, and a matching Include filter. (the include filter is one line that encompasses all of the IPs from all defined channels). Like this:

(DestinationIP[] or DestinationIP[])

(SourceIP[] or SourceIP[])

Incude filter
(IP[] or IP[]) 

Our question is, are we hurting or helping machine performance by using the include filter since it is essentially a duplicate of the channel definitions?

custom-sensor netflow performance

Created on May 26, 2010 2:00:49 PM

Last change on May 27, 2010 6:19:47 AM by  Daniel Zobel [Product Manager]

1 Reply

Accepted Answer



The difference is negligible.

When using the include filter, the data stream is filtered at an early stage. As such, less data is processed by the channel definitions. This largely depends on the type of data and the filter used. Generally, these filters are rather "quick," therefor there is no need to worry about performance issues as regards filtering parameters. Other NetFlow sensor options (such as toplists) use up a lot more resources.

Created on May 27, 2010 10:23:47 AM by  Patrick Hutter [Paessler Support] (7,225) 3 3

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.