reconnect failed, database down? -> sql returned ok for two times before failover

Hello, i want to configure a mysql db failover. In my tests it seems that if the first mysql db is not reachable the first two authentication attempts are rejecting the user, because the rlm_sql module returns ok and no failover will happen. The module recognised that the db is not reachable but returns ok. On the thrid attempt the server switched to the redundant second db. Is this the deliberate behavior? Is there a way to switch direct to second db if the first db fails or are the two rejects mandantory before failover? Thank you Andreas Engler