All-in-One NetFlow Analyzer PRTG

What is NetFlow?

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 protocol is mainly supported by Cisco routers and switches.

With the PRTG NetFlow Analyzer you can get a holistic view about your network and what your bandwidth is being used for.

“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.

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.

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

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.

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.

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 n^th 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. 

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.

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.