-----------operations-----------
?The log file currently supervised is deleted.
?All the events of same trigger disappeared from on the event page.
?I created new log file.
?The event of the trigger which had disappeared from the event page was displayed again.
-----------operations-----------

If items are in unknown state, events are not displayed on event page.
This means we cannot understand what items were changed to unknown and cannot check old events either.

For example, We cannnot check the event in situation ?, and it is inconvinient.

On the event page, CTrigger is used with the monitored option for narrowing down triggers.
Therefore, when item changes into unknown state temporarily, we cannot check in some events.

When the monitored option is used by CTrigger,
events are narrowed down by triggers included active items but should triggeres included unknown item be included, either?