All-in-One NetFlow Analyzer PRTG


  • NetFlow Analyzer PRTG monitors your bandwidth & traffic
  • PRTG supports all different NetFlow versions
  • PRTG monitors all important Flow protocols


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No limitations for 30 days
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100 Sensors, perfect for small networks

This is how NetFlow monitoring with PRTG works







NetFlow protocol is mainly supported by Cisco routers and switches.

NetFlow lets you analyze and monitor your bandwidth and determine, for example, the amount of traffic caused by IP addresses, protocols, or programs. In order to carry out such an analysis, you'll configure your routers such that flow packets are sent to a computer installed with a PRTG probe. Flow technology puts little strain on your CPU and is especially adapted for networks with heavy data traffic.


NetFlow Monitoring software, without any additional costs.

no need for upgrades

No upgrade necessary

PRTG is an all-in-one package! Our network monitoring tool requires no additional upgrade or tool to analyze your bandwidth using Cisco NetFlow. All it takes is a standard PRTG installation and you’ll be on your way to monitoring the entire traffic which passes via your routers and switches.

all in one

One tool for everything

With PRTG, you get one central software solution for all of your monitoring – and a complete overview. The need for a combination of many different tools is a thing of the past. PRTG lets you monitor your bandwidth use, server, CPU, website, cloud services, and much more. Try the NetFlow collector for yourself.

Auto Discovery

Quick installation

PRTG uses Auto Discovery to automatically set up comprehensive monitoring, and creates all the sensors you need. Switching from other monitoring software to PRTG therefore takes no time at all.



By default, Toplists in PRTG always split up the traffic within the sensor among Top Talkers (bandwidth use according to IP address), Top Connections (according to connection), and Top Protocols (according to protocol). With Toplists, you’ll enjoy a categorized overview which makes NetFlow traffic analysis easy.

PRTG sensors for NetFlow monitoring



NetFlow version 5 is in widespread use. With PRTG, you get a compatible NetFlow V5 sensor, as well as a NetFlow V5 custom sensor.




NetFlow version 9 is an advanced form of NetFlow technology. PRTG provides you with appropriate sensors for its use: the NetFlow V9 sensor and NetFlow V9 custom sensor.




Internet Protocol Flow Information Export (IPFIX) is an advanced form of Cisco's NetFlow system. PRTG offers two sensors for its use: The IPFIX sensor and IPFX custom sensor, which you can customize to meet your own specific needs.

This is what NetFlow monitoring looks like in PRTG

NetFlow Analyzer PRTG
3 useful applications  

PRTG lets you recognize if your switches are not equipped to handle the quantity of data of your backup solution.
Before they become completely overloaded.
Should these switches overload during a backup anyway, PRTG will enable you to quickly find the perpetrator.


Identify bandwidth hogs

Individual sources often use disproportionately high amounts of bandwidth. These sources may be individual users, but also programs or specific data. With our NetFlow monitoring software, you’ll evaluate IP addresses and analyze netflow traffic.

Spot load peaks early

Many companies experience fluctuations in access to various websites or internally-used applications. Define your own thresholds so you can be informed early: ideally, before the performance of your system takes a hit.


Avoid backup overloads

Thorough backups can lead to problems for the entire network. Such problems are frequently the result of individual routers or switches which overload during the backup and thwart the entire network. Use NetFlow Analyzer PRTG to monitor and find the causes, and thereby optimize your network.


“We can all work with greater peace of mind knowing that our systems are constantly being monitored.”

Markus Puke, Network Administrator at the Schüchtermann-Klinik.



Let our free NetFlow Monitor work for you,
so you can concentrate on your day-to-day tasks with total peace of mind.


With PRTG, you get one central monitoring tool with which to monitor your bandwidth and network via NetFlow, SNMP, or Packet Sniffing. Enjoy a quick and easy overview thanks to our dashboards and maps.


Customizing PRTG is a breeze. When it comes to NetFlow analysis, you’ll get all the right sensors in their many different forms. And this will save you time as your get your monitoring up and running.


PRTG is worth it. 80 % of our customers report savings in the area of network management. And the respective costs for our PRTG licenses pay for themselves in an average of only 3 ½ months.

Practical tip: “Hey Gerald, what would you tell administrators looking to use PRTG to monitor their NetFlow?”

“Cisco has continuously developed NetFlow technology. Administrators must therefore find out beforehand which NetFlow version is supported by their routers and switches. With the right PRTG sensors, setting up NetFlow monitoring is quick and easy.”

Gerald Schoch works as a technical editor at PAESSLER AG.

NetFlow Analyzer PRTG:
Setup in 3 simple steps!



Configure the router's NetFlow protocol so it sends NetFlow packets to the computer running the PRTG Network Monitor:

Step 1

Install PRTG. Flow sensors are even available in PRTG's Free Trial Version. Choose a suitable license to enjoy comprehensive monitoring with over 100 sensors. You can also do this at a later time.

Step 2

Configure your Cisco router or switch so that it exports and sends NetFlow data to a computer running a PRTG probe. In the next step, you'll create the NetFlow sensor on this computer. Pay special attention to the Flow version which is exported, for a compatible sensor must be used in PRTG.

Step 3

Create NetFlow sensors which are appropriate for the exported Flow version and target address and configure the UDP port and an IP address in the sensor settings where you would like the flows to be received. Another option is to indicate the IP address of a specific Cisco device if you would like the flows to be received by such a device, and turn on sampling mode if you have set this mode on the target device. Enter a value for the Active Flow Timeout which is at least one minute longer than that of the device. Finally, choose which of the sensor's data traffic categories should be displayed in the various channels, and define an optional filter for the desired data.


Alternative: If you do not require long-term analyses for every single PC and would only like to monitor the traffic occurring presently and recently on the basis of IP or protocol, then creating a NetFlow sensor and correspondingly analyzing the data traffic in the Toplists based on IP or protocol is sufficient. More information on setup: search answers to user questions in our Knowledge Base. In this article, you'll find additional tips on the configuration of Cisco routers.

Netflow Monitoring for VMware


VMware and NetFlow: VMware uses NetFlow technology in the "vSphere Distributed Switches (vDS)" product line. In principle, these virtual switches connect the virtual network cards of virtual machines (VMs) to the network by way of the physical network cards of hosts. VMware has incorporated NetFlow for these virtual switches. 

Monitoring with PRTG: Both monitoring and the NetFlow monitoring of physical (Cisco) devices are operational here. Set up NetFlow in the VMware vCenter and configure it such that these flows are sent to PRTG, where a corresponding flow sensor displays and monitors the data. As long as the correct NetFlow version is used, it will make no difference to PRTG where the flows come from.

Further Information:

Over 95% of our customers recommend PRTG

Paessler AG submitted an extensive survey to more than 600 IT departments worldwide who use PRTG. The goal of this survey was to optimize and fine-tune our Network Monitoring Software to better meet the needs of administrators. One survey result: more than 95% of the participants would recommend PRTG - or have already done so.


Other Flow sensors


PRTG provides other Flow sensors which allow you to monitor your chat protocols, Citrix, FTP, Email, and other traffic.

sFlow: With an sFlow sensor, only every nth packet will be passed on: this results in even less load on the system. Find our more about the PRTG sFlow sensor here.

jFlow: jFlow lets you monitor Juniper Networks hardware, among others. Here too you can configure devices especially for PRTG. It features a high degree of similarity to NetFlow5. Find out more about our jFlow sensor

Award winning solution

We work hard on making our software as powerful and easy-to-use
as possible for our customers each and every day.
Of course it makes us proud when we get awards for that.



Comparison: Netflow, SNMP, Packet Sniffing


SNMP: SNMP (Simple Network Management Protocol) is extremely popular and an easy way to read device data. It gives you an important first look, e.g. on bandwidth use, CPU, or the temperature of your hardware. More on SNMP monitoring with PRTG

Packet Sniffing: For more detailed information on your bandwidth usage, use Packet Sniffing or NetFlow. You will thus be able to take a closer look at the packets passing through individual routers or switches. More on Packet Sniffing with PRTG.

NetFlow Analysis: NetFlow is a protocol supported in particular by Cisco hardware. You therefore need a monitoring solution which is compatible with NetFlow. Such a solution (Packet Sniffing, e.g.) will enable you to analyze packets in detail. PRTG comes with a set of NetFlow sensors - at no extra charge.



“Our top priority is to continue to develop PRTG is a constant, practical, and proactive manner. Our hope is that administrators will always be ready for any new standards which arise.”

Dirk Paessler, founder and Director of Paessler AG in Nuremberg.

How much will Netflow Monitoring
with PRTG cost?







Installed in minutes
Free Version
100 Sensors, perfect for small networks



Many administrators compare NetFlow analysis and bandwidth monitoring tools.

PRTG boasts: 

100 free sensors: are you the administrator of a small business or organization? With PRTG, you get 100 free sensors which never expire! This is an interesting option even for those administrators who are in charge of larger networks. There are no strings attached - take your time trying PRTG to see if it is the right tool for your needs. Our NetFlow sensors are included!

Flexible upgrades: sold on PRTG? Find a license that caters to your demands and the size of your network. Should your company or NetFlow Analyzer needs grow, then upgrading with a suitable license is quick and easy.

PRTG is worth it: network failures come with high price tags. Conversely, this means that by increasing reliability, you'll save hard cash. Paessler AG has been carrying out customer surveys for many years. The results speak for themselves: 46% report significant to outstanding cost savings. 64% indicated that they save a great deal to an exceptionally great deal of time by using PRTG.

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