Slim Application Error

The application could not run because of the following error:

Details

Type: PDOException
Code: 2002
Message: SQLSTATE[HY000] [2002] No such file or directory
File: /var/www/stellwerk-heide.de/www/src/app/controller/BuchenController.php
Line: 81

Trace

#0 /var/www/stellwerk-heide.de/www/src/app/controller/BuchenController.php(81): PDO->__construct('mysql:host=loca...', 'stellwerk', 'DKyPpHBs3m0x')
#1 [internal function]: BuchenController->index(Object(Slim\Http\Request), Object(Slim\Http\Response), Array)
#2 /var/www/stellwerk-heide.de/www/vendor/slim/slim/Slim/Handlers/Strategies/RequestResponse.php(40): call_user_func(Array, Object(Slim\Http\Request), Object(Slim\Http\Response), Array)
#3 /var/www/stellwerk-heide.de/www/vendor/slim/slim/Slim/Route.php(281): Slim\Handlers\Strategies\RequestResponse->__invoke(Array, Object(Slim\Http\Request), Object(Slim\Http\Response), Array)
#4 /var/www/stellwerk-heide.de/www/vendor/slim/slim/Slim/MiddlewareAwareTrait.php(117): Slim\Route->__invoke(Object(Slim\Http\Request), Object(Slim\Http\Response))
#5 /var/www/stellwerk-heide.de/www/vendor/slim/slim/Slim/Route.php(268): Slim\Route->callMiddlewareStack(Object(Slim\Http\Request), Object(Slim\Http\Response))
#6 /var/www/stellwerk-heide.de/www/vendor/slim/slim/Slim/App.php(503): Slim\Route->run(Object(Slim\Http\Request), Object(Slim\Http\Response))
#7 /var/www/stellwerk-heide.de/www/vendor/slim/slim/Slim/MiddlewareAwareTrait.php(117): Slim\App->__invoke(Object(Slim\Http\Request), Object(Slim\Http\Response))
#8 /var/www/stellwerk-heide.de/www/vendor/slim/slim/Slim/App.php(392): Slim\App->callMiddlewareStack(Object(Slim\Http\Request), Object(Slim\Http\Response))
#9 /var/www/stellwerk-heide.de/www/vendor/slim/slim/Slim/App.php(297): Slim\App->process(Object(Slim\Http\Request), Object(Slim\Http\Response))
#10 /var/www/stellwerk-heide.de/www/public/index.php(52): Slim\App->run()
#11 {main}