Forum Discussion

Dmitry's avatar
8 years ago

"No Data" alerts

Recently we enabled “No Data” alerting for the data source "Tomcat JVM status-", data point "JVMUptimeMinutes". This data point has also the alert threshold set <= 30.

On the process restart we received “No Data” alert, this is a good point. The alert was active till the time “JVMUptimeMinutes” had passed the threshold 30 minutes. The problem is that all this time LM continued to display “No Data” in the column “Value” (the “Alerts” tab) for this device though LM was getting real data. This was really confusing.

I am summarising results of our discussion with LM tech support:

- Internally there is only one object called "Alert".
- This object can be triggered either by 'no data' or 'threshold' conditions.
- The 'Value' column contains the reason of the alert: 'no data' or a numeric value.
- The object exists either until a numerical value passes the threshold if it is set, or it clears when LM starts getting data if there is no threshold. 

It would be great if the 'Value' column displayed the current value in addition to the condition triggered the alert, something like 16.54 ('No Data'). This would help to avoid possible confusion.

  • Check to see if the SNMP "Host Agent" was running at all during that time: or if the System was running DRF at the time of the problem.

     

    When dealing with CUCM : one constant I see is that DRF stops and starts services at will.....so all alerting should be disabled during DRF scheduling.

     

    - M