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Monitor multiple values with subtractions in one graph?



I am monitoring multiple switchports as separate sensors in PRTG today. I simply monitor the bandwidth of data on each cisco-switchport. But I want to do something more complex than that.

Lets say that switchport X is a trunk containing a lot of traffic from different sources and switchport Y and Z are two different switchports that contains a subset of the traffic load on X. Traffic comes from port Y, Z and a lot of other ports and it is all going into switchport X.

I want to have one single graph with multiple values stacked on top of each other, like this:

Green: Traffic load on port Y Blue: Traffic load on port Z Red: Traffic load on port X - Y - Z

Is this doable?


prtg smtp traffic-monitoring

Created on Nov 9, 2010 8:13:34 AM

1 Reply




this can be done with a sensor factory sensor.

please take a look at


Created on Nov 9, 2010 10:46:21 AM by  Aurelio Lombardi [Paessler Support]

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