Wp_Schedule_Event every day at specific time

Question

WP Cron runs, when somebody visits your website.
Thus if nobody visits, the cron never runs.

Now there are 2 solutions:

Disable WP Cron, use a real cron job and customize it.

https://support.hostgator.com/articles/specialized-help/technical/wordpress/how-to-replace-wordpress-cron-with-a-real-cron-job

Use a custom interval in wp_schedule_event():

function myprefix_custom_cron_schedule( $schedules ) {
    $schedules['every_six_hours'] = array(
        'interval' => 21600, // Every 6 hours
        'display'  => __( 'Every 6 hours' ),
    );
    return $schedules;
}
add_filter( 'cron_schedules', 'myprefix_custom_cron_schedule' );

//Schedule an action if it's not already scheduled
if ( ! wp_next_scheduled( 'myprefix_cron_hook' ) ) {
    wp_schedule_event( time(), 'every_six_hours', 'myprefix_cron_hook' );
}

///Hook into that action that'll fire every six hours
 add_action( 'myprefix_cron_hook', 'myprefix_cron_function' );

//create your function, that runs on cron
function myprefix_cron_function() {
    //your function...
}

and you can see these tuts

http://www.nextscripts.com/tutorials/wp-cron-scheduling-tasks-in-wordpress/

http://www.iceablethemes.com/optimize-wordpress-replace-wp_cron-real-cron-job/

http://www.smashingmagazine.com/2013/10/16/schedule-events-using-wordpress-cron/

custom Wp cron

http://codex.wordpress.org/Plugin_API/Filter_Reference/cron_schedules

http://www.smashingmagazine.com/2013/10/16/schedule-events-using-wordpress-cron/

http://www.viper007bond.com/2011/12/14/how-to-create-custom-wordpress-cron-intervals/

http://www.sitepoint.com/mastering-wordpress-cron/

https://tommcfarlin.com/wordpress-cron-jobs/

http://www.paulund.co.uk/create-cron-jobs-in-wordpress

cron linux