Changes made to the CA NFA harvester.parameter_descriptions table.
In 9.3.3 and earlier, there was a Realtimereaper_runAlarms setting in the harvester.parameter_descriptions table that needed to be set to '1' in or order for the Reaper to send traps.
If you have that settings set to 1, it will cause the Reaper to crash in NFA 9.3.6 and later.
In 9.3.6 there is a new parameter named Reaper_RunAlarms which now needs to be set to 1 instead, in order to send traps.
You can verify this with the query below:
mysql -P3308 -D harvester -t -e "select * from parameter_descriptions where parameter='RealtimeReaper_RunAlarms';"