Hi TrickyRaccoon92

... would any running experiment keep a cache of to-be-sent-data, fail the experiment, or continue the run, skipping the recordings until the server is back up?

Basically they will keep trying to send data to server until it is up again (you should not loose any of the logs)

Are there any clever functionality for dumping experiment data to external storage to avoid filling up the server?

You mean artifacts or the database ?