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SNMP Sensor - Custom Lookup



Hi, I currently have SNMP monitoring the Windows Update Service in XenApp 6.5. For the obvious reasons, Windows Update should not be running. However, from time-to-time, System Center Endpoint Protection will activate the service when it performs its update and sometimes, the service remains running.

I have a Value Lookup as such:

	<SingleInt state="Ok" value="0">
	  <SingleInt state="Error" value="1">

Basically, if Windows Update is stopped or disabled, this should be flagged as 'OK'.

If Windows Update is running, this should be flagged as an 'Error'.

However, employing the above, if WU is running, it's listed as OK, and if its down, it's listed as 'Error'. I need the opposite to happen.


custom-sensor lookups snmp

Created on Jul 1, 2015 3:19:19 AM

Last change on Jul 2, 2015 8:42:30 AM by  Luciano Lingnau [Paessler]

1 Reply



Your logic (Using Lookups) is correct but unfortunately there's an issue:

The way SNMP works, once a service is stopped it is removed from the SNMP svSvcTable, that way the SNMP Windows Service Sensor will throw an exception/error:

This service is either not installed on the target system or it is stopped. To monitor a service and make sure that it is NOT running, see https://kb.paessler.com/en/topic/64529. (code: PE207)

To monitor a service and ensure that it is stopped, please check the ServiceStatus sensor from PRTG Tools Family.

See this thread for details:
64529 - Is there a method to ensure something DOESN'T exist?

Best regards,

Created on Jul 2, 2015 12:15:17 PM by  Luciano Lingnau [Paessler]

Last change on Nov 29, 2019 11:21:00 AM by  Maike Guba [Paessler Support]

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.