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Subtract penultimate measurement from last measurement

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0

Hi, I have a sensor, wich measures an increasing value. Now I want to devide the newest mesurement from the last one to get the number how much it increased this time. I cant find a way to do this with a factory sensor.

X = B-A

/ <-- B
/ <-- A
/
/
/_____________

Is there a way this could be solved?

Thank you :)

measurement penultimate snmp

Created on Oct 12, 2017 9:34:37 AM



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Accepted Answer

Votes:

0

Hi, This sounds like a good scenario for spike filters to ignore these unreasonable values. Click on the gauge symbol to enter the channel settings and choose Spike Filter | Enable Filter.

Created on Oct 13, 2017 8:59:34 AM by Felix Saure [Paessler Support]



3 Replies

Votes:

0

Hi there,

Basically, most custom sensors offer the possibility to change the unit for each channel. You can change the unit to Delta so that PRTG only returns the difference.

Does that help you?

Best regards, Felix

Created on Oct 12, 2017 11:51:42 AM by Felix Saure [Paessler Support]



Votes:

0

Hi,

normally I use the "delta" function but the "SNMP Custom" sensor I use gets values about 4'250'000'000 new SSL connections/s - even when the device I monitore is not even used. Than the grpah looks like:

_____/\_________/\___/\___________

... over 2 days. Normally there is 0, but sometimes it fails and gets a very huge measurement. An other device I use also gets that huge values. Default values are about 100 to 150, sometimes its 1'4xx'xxx'xxx and more.

Thank you for helping :) Maby we can find a bug in the "Delta" function.

Created on Oct 12, 2017 12:14:15 PM



Accepted Answer

Votes:

0

Hi, This sounds like a good scenario for spike filters to ignore these unreasonable values. Click on the gauge symbol to enter the channel settings and choose Spike Filter | Enable Filter.

Created on Oct 13, 2017 8:59:34 AM by Felix Saure [Paessler Support]




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