bootstrap.php:

    Cron::set('search_index', array('0 * * * *', function(){
        $indexer = new Search_Indexer();
        $indexer->execute();

        exec('indexer --config application/config/wc_search.conf --all --rotate');
    }), 'search');


crontab:

    * * * * * php -f application/modules/cron/run.php search