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How do flow sensors work in a clustered environment?



If I understand PRTG clustering properly, each node has an exact copy of the master node's sensor configurations. What happens then with flow or packet collection sensors configured on the master node? If the master node is collecting its own packets, do the failover nodes also need to be collecting packets? How about for netflow exported from a router? Does the netflow exporter need to send the same flows to all nodes in the cluster? What happens on the fail over node if it has a flow sensor configured but does not receive flow data?

clustering custom-sensor flow prtg8

Created on Sep 15, 2010 6:16:28 PM

Last change on Dec 2, 2021 8:21:54 AM by  Maike Guba [Paessler Support] (2,404) 2 1

2 Replies



Dear Jim,

Flow Sensors and Packet Sniffers can only be used on the Local Probe of the Master Node or on Remote Probes connected to the Master Node. Failover Nodes cannot be used with such sensors.

Created on Sep 16, 2010 11:49:33 AM by  Torsten Lindner [Paessler Support]

Last change on Dec 2, 2021 8:22:08 AM by  Maike Guba [Paessler Support] (2,404) 2 1



I'm not sure I understand. A failover cluster node is a clone of the master node, correct? If I configure flow sensors on the master node aren't they also cloned onto the failover node(s)? What do the failover nodes do with these sensors?

In a previous netflow and clustering question on this forum it was indicated that if the master was down for part of a reporting period, a report could instead be generated using the "all nodes" function. This indicates that the failover nodes would have data in their flow sensors but above you indicate that those sensors may note even exist on the failover node.

Can you clarify the situation please?

Created on Sep 16, 2010 1:06:01 PM

Last change on Dec 2, 2021 8:22:27 AM by  Maike Guba [Paessler Support] (2,404) 2 1

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