Warning: require(/var/www/html/magento2/pub/../app/bootstrap.php): Failed to open stream: No such file or directory in /var/www/html/magento2/pub/index.php on line 12

Fatal error: Uncaught Error: Failed opening required '/var/www/html/magento2/pub/../app/bootstrap.php' (include_path='.:/usr/share/php') in /var/www/html/magento2/pub/index.php:12 Stack trace: #0 {main} thrown in /var/www/html/magento2/pub/index.php on line 12