Netflow Monitoring
NetFlow Sensors for PRTG Network Monitor
Beyond normal bandwidth monitoring capabilities based on SNMP, PRTG allows administrators to discern actual bandwidth usage based on multiple parameters, such as IP addresses, port numbers, protocols, etc., using NetFlow collector sensors.
The NetFlow protocol is supported by most Cisco routers and certain Cisco switches in order to measure bandwidth usage. These devices can be configured to send data streams with the network's usage data to the machine running PRTG which can then analyze the data. PRTG's NetFlow collectors receive data forwarded by NetFlow-capable Cisco devices using NetFlow collector licenses (available as PRTG add-ons).
As such, NetFlow can give you information on where, why, how and by whom specific applications are being used and how the usage might affect the network.
The configuration and implementation methods are outlined below.
Configure the NetFlow protocol on the router to send NetFlow packets to the computer running PRTG
- (Purchase and) install Netflow Collector License (also works with trial license)
- Configure a Netflow collector in PRTG
- Create one new NetFlow sensor for each IP or protocol to be monitored and apply a filter based on the IP or protocol for each item you want to monitor
- Or: If you do not need long term accounting data for each PC and only want to know the current and recent traffic by IP or protocol, you can create just one NetFlow sensor and enable the Toplist feature based on IP or protocol.
Note: If you have several switches/routers you may not see all traffic if you only monitor one device
Further information on setting up Netflow sensors can be found here.