So, I wanted an complete secure Moodle E-learning environment.. After completing the installation fully non-secure (HTTP) , I fiddled with al the configuration settings.. Seems there is no immediate logical / direct way for getting this done..

For reference, getting Moodle  on Nginx working completely secure (full SLL)

1) config.php –> change $CFG->wwwroot   = ‘https://yourmoodleurl’;
2) Disable HTTPS login under Administration –> Security –> HTTP
3) config.php –> add  $CFG->sslproxy=true;

And ofcourse change your nginx server/site configuration