We recently noticed in some of our production environments that there are several cleared state events with no associated active event. These events all appeared at the same time, one for each tag we had alarms configured for, including alarms that were disabled, this happened several times during the course of the last weeks.
The issue is similar to some others already in this forum:
- Orphaned Alarm Event Data in datasource alarm_events table
- Multiple instances of one alarm event without transition to any other
- Alarm Cleared but Never Active - #4 by jacob.ramirez
However we did not recently update Ignition's version (which is currently 8.1.37), nor modified UDTs.
From the data provided by the historian, we were able to verify that the alarms should have never been active, meaning the issue is not about active events missing, but rather about cleared events seemingly appearing out of nowhere.
There seems to be a weak correlation between these events appearing and gateway restarts, however sometimes they appear without the gateway restarting, sometimes they don't appear despite the gateway restarting.
We can confirm the clear events are present in the database as well:
Can these events be safely ignored, or are they caused by something specific?
