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NetApp snmp monitor



We are using PRTG to monitor our NetApp but are having trouble that PRTG Displays negative numbers for larger values which makes the monitoring quite useless.


monitoring netapp smtp

Created on Nov 17, 2010 3:27:29 PM

3 Replies



This seems to be an overflow. This shouldn't occur if you use 64-bit counters (SNMP v2c).

Created on Nov 18, 2010 1:34:52 PM by  Patrick Hutter [Paessler Support] (7,225) 3 3



Hi, You are probably right about the overflow. I tried using another tool for monitoring and got the same negative value, it seems like its the snmp definition from NetApp that is "wrong" somehow. Later on i found that other people with netapp - on their forums had same troubles.

But I found a workaround, by using custom sensors and using a batch-file, a command linke snmp-get, and a pythonscript.... And adding 4294967296 if the number is negative.

Its manageble defining these custom sensors for just two sensors i need to monitor, but i really would need to monitor about 10-30 sensors to get a good overview of the disk usage.

It would be really nice if one could do a bit math directly in the sensors, since i dont think its possible to always have right values from snmp.... And some of the result values from my netapp are divided in two different snmp-fields that eventually needs to be added together to make sens.

Created on Nov 18, 2010 1:46:44 PM



Create a new SNMP Custom sensor, and select value type "Gauge - signed"

Created on Feb 17, 2012 4:47:27 PM

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