The dashboard_engine is only needed if you are still using the old flash dashboards. Since 8.4 these are no longer supported.
However, if you upgraded it may still be running and addressed in wasp and you may be seeing error like
Feb 25 07:17:48:853 INFO [pool-1-thread-1, com.nimsoft.nimbus.probe.service.wasp.udm.StatusCheckThread] UDM not initialized yet. Trying to initialize.
Feb 25 07:17:48:855 WARN [pool-1-thread-1, com.nimsoft.nimbus.probe.service.wasp.udm.UDM] Unable to initialize data update from dashboard_engine.
You can disable/delete the dashboard_engine probe from IM or AC but you will also need to make sure there is no reference to them in wasp.
You can do this
a) in the GUI - <Setup> in the lower section that says Probe Addresses.
There is a field dashboard_engine with a value dashboard_engine, or the address of the dashboard engine.
Remove the value and restart wasp and you should no longer receive the error messages in the wasp.log.
b) you can delete the key dashboard_engine in raw configure or modify the field in wasp.cfg by deleting the line:
dashboard_engine = dashboard_engine