Rwsplit handles ERRACT_NEW_CONNECTION by clearing backend reference, removing callbacks and associating backend reference with new backend server. If it succeeds and the router session can continue, handleError returns true. Otherwise false. When ever false is returned it means that session must be closed.
Rwsplit now tolerates backend failures in a way that it searches new backends when monitor, backend, or client operation fails due to backend failure.
Maintenance mode prevents a server from having new connections made
to it and stops MaxScale from monitoring a server. It is designed
to allow a server to be taken out of an active cluster for maintenance.
It prevents new connections and allowsg existing connections to
drain away prior to performaing maintenance on the server.
