Enhance the user experience of automated log upload when one or more nodes is down

I'm not sure what the best solution is, but opening this to start the discussion and track.

If a node is down and/or can't generate its logs for some reason, it would be good to inform the user how to accomplish that. Perhaps a descriptive message alongside the failed node (in the UI and the REST/CLI output?) indicating what they should do.

Obviously if a node is down, that's the most likely one we would actually want logs from