Just regarding the .conf file methodology it tries to connect when the gateway starts up but if the connection is lost while the GW is running it will not retry and as far as I can tell (I asked if there was a way to retry programatically via a GW script) it does not seem like there is a way.
Highly recommend using one of the other options Phil listed instead of trying to make the .conf login method be more robust - doesn't seem possible.