CakePHP: Warning: _cake_core_ cache was unable to write 'cake_dev_en-us' ...

Este error me dio al acceder el sitio después de clonar una copia fresca del framework:

Warning: _cake_core_ cache was unable to write 'cake_dev_en-us' to File cache in /var/www/html/cakephp/lib/Cake/Cache/Cache.php on line 310 Warning: /var/www/html/cakephp/app/tmp/cache/persistent/ is not writable in /var/www/html/cakephp/lib/Cake/Cache/Engine/FileEngine.php on line 337

Evidentemente es un error de permisos que solucioné cambiando el usuario owner del proyecto al del servidor web que en este caso es 'apache':

chown -R apache:apache /var/www/html/cakephp