When Automatic Incident tracking is enabled, alarms are grouped. These “Alarm Group” alarms are basically new alarms, but they do not always have an alarmID that is equal to their root alarm ID.
What is the meaning of this difference?
Do alarm trees of alarm groups exist?
Alarm groups form alarm trees just like regular alarms. Upon creation the alarm group has an alarm ID equal to the root alarm ID. Every update to the alarm group then gets a new alarm ID, but keeps the initial root alarm ID.
Alarm groups receive updates whenever base alarms are added or removed, the display value (explaining the contents of the group) changes or the group is masked or unmasked.
There is no way to “close” alarm groups. They are fully managed by the Analytics process, that automatically clears them when their base alarms are cleared, or when no more reason for grouping exists.
Although some alarm group trees could grow substantially in particular circumstances, Analytics will limit the number of actual updates to the bare minimum at all times.
And is there a way to “close” this tree of alarm groups? Normally we discourage alarm trees that get too big without ever getting cleared, but as these alarms are not tied to any specific parameter it may be impossible to ever clear them directly.