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Cannot get bandwidth with GRE encapsulation by sflow



Hi , I have use sflow to monitor my device, and found two things:

1.I cannot get bandwidth if the traffic is thought GRE tunnel.

2.The bandwidth information seem not inaccurate, I have compare with device interface and another flow collect software(NetFlow Analyzer by ManageEngine), the bandwidth volume of PRTG seem always more then about 10M, I also have add filter by inboundinterface ,outboundinterface and IP address.

May I know how can I get bandwidth with GRE encapsulation ? and how can I add filter for specific IP and interface let the bandwidth volume more accurate ?

bandwidth sflow tunnel

Created on Nov 23, 2016 3:15:12 AM

1 Reply



Hi there,

Unfortunately, SFlow is only able to monitor UDP and TCP based traffic. This would explain why you see this low bandwidth usage. Additionally, this Site describes what filters can be used for the Flow and Traffic-Sniffer sensors.

Created on Nov 25, 2016 10:11:43 AM by  Dariusz Gorka [Paessler Support]

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.