Fatal error: Maximum execution time of 30 seconds exceeded in Drupal

Increase PHP's memory limit:

ini_set('max_execution_time', 100); in your sites/default/settings.php file

----php.ini -------------------------------------------

max_execution_time = 100 ; Maximum execution time of each script, in seconds

max_input_time = 60 ; Maximum amount of time each script may spend parsing request data

Enjoy ubuntu... ;)