rdiff test_connection fails for no reason
Our rdiff backups often randomly fail because of connection tests, but our connection works all the time. If we disable connection tests with
testconnect = no the backups succeed every time. I've checked the test_connection function and it looks simple enough. There is no relevant output in any logs, even at the highest debug level, and with the addition of ssh -vvv. Perhaps a more robust test might be better.