As you all may/might not know, the dashboard of test run having useful graph from influxdb data in the host controller machine during testing. 

After the test finished, the dashboard will still point to the influxdb of the controller machine.
this causing issue if controller are offline/removed then we will lost the graph data and the test results will not have the online graph anymore.

Any normal user, would have a common expectation of the same graph always available during test run and after test run.

So it would be best to process and saved related influxdb bucket after each test run, into centralized LRE influxdb for availability of the graph.

i also make the discussion over here if you're interested to follow:
(+) How to set Infinite retention for Test Run Data Graph ? The LRE are are automatically purging our test graph data !! - LoadRunner Enterprise User Discussions - LoadRunner Enterprise (microfocus.com)