Here is the description from our AOS Command Reference Guide.
Use the event-history on command to enable event logging for the AOS system. Event log messages will
not be recorded unless this command has been issued (regardless of the event-history priority
configured). The event log may be displayed using the show event-history command. Use the no form of
this command to disable the event log."
If you do a search on the forum for AOS Command Reference Guide you can download it and search for commands.
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