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Disk Transfers per Second Sensor Sensor



I have created a custom WMI sensor to monitor disk transfers per second on a selected disk using the SQL script:

SELECT DiskTransfersPersec FROM CPQ_PhysicalDisk WHERE PhysicalDisk Like '%F:%'

If the sensor returns any value higher than 0 it errors.

Example error: '16.9246711730957' is not a valid integer value

The value is the correct reading, however why does it state that it is not a valid integer value?

Thanks James

custom-sensor iops prtg wmi

Created on Mar 3, 2010 9:54:50 AM

Last change on Apr 29, 2010 9:39:41 AM by  Daniel Zobel [Product Manager]

3 Replies

Accepted Answer




WMI custom sensors are limited to integer values and your counter returns a floating point value. That's the reason for the error.

Unfortunately there is no way in WQL to truncate or round a floating point value, so there is nothing you can do at the moment to get this WMI counter working.

Instead please try to find a counter that returns an integer value, e.g. a counter that returns a "counted" value (kilobyte, packets, etc.), not a value that is already divided by a time measurement (kilobytes per second, packets per second, etc.).

We'll integrate support for floating point values in a future version.

- Volker

Created on Mar 3, 2010 1:11:55 PM by  Volker Uffelmann [Paessler Support]

Last change on Mar 3, 2010 1:15:35 PM by  Dirk Paessler [Founder Paessler AG] (11,025) 3 6



A possible alternative to using WMI for Disk Transfers per Second would be an SNMP Library sensor using SNMP Informant. As long as the SNMP Informant agent is installed on the server being monitored.

I have found that the freeware version of SNMP Informant gives me access to all of the disk usage counters like Reads, Writes, and Transfers per second as well as Disk Queue Length.

Jason Luedke

Created on Mar 3, 2010 6:29:16 PM

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