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Send notification only if 2 hosts are down



We have remote sites that 4 hosts but I want to receive a notification only when 2 of the 4 hosts are down (cannot ping them at the same time), so how can we archive this with PRTG (verion 8)?


email notifications ping

Created on Jul 30, 2011 9:04:39 AM

2 Replies



This can be done with Custom Sensor PTF.SensorCount

With this sensor you can count the number of down sensors (or any other state) in a particular group.

So if you place the ping sensors of your 4 hosts in one group, PTF.SensorCount will tell you how many of them are down.

Enabling limits of this sensor (in the channels tab) will let you determine when a notification is send.

Created on Jul 31, 2011 9:28:38 AM



You could do this by writing a script that pings all 4 servers and adds 1 to a variable for each server that replies. Export that variable in brackets to a web page and use an HTTP sensor to read and plot that variable. Then you can set an alert on that HTTP sensor to notify you if the total count falls below 3.

In pseudo-code:

Count == 0
If (return value of ping) = 0   /*Successful ping*/
  then Count == Count +1

echo "[" Count "]" > PingCount.html


Created on Aug 1, 2011 2:53:26 PM

Last change on Aug 1, 2011 3:15:07 PM by  Torsten Lindner [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.