Set chmod -R o + w rights to the storage and bootstrap/cache directories laravel code example
Example 1: laravel storage folder permissions
cd [..LARAVEL PROJECT ROOT]
sudo find . -type f -exec chmod 644 {} \;
sudo find . -type d -exec chmod 755 {} \;
sudo chmod -R 777 ./storage
sudo chmod -R 777 ./bootstrap/cache/
Example 2: proper permission webserver laravel
sudo chmod -R 777 path/to/root
sudo chown -R www-data:www-data /path/to/root
sudo usermod -a -G www-data ubuntu
sudo find /path/to/root -type f -exec chmod 644 {} \;
sudo find /path/to/root -type d -exec chmod 755 {} \;
sudo chgrp -R www-data storage bootstrap/cache
sudo chmod -R ug+rwx storage bootstrap/cache