HAproxy is a great load balancing solution that we use at Instela. We use HAProxy in a 8-Cores bare metal machine and we also use it to offload SSL encryption.
As we all know, Zend Framework 2 handles 404 not found event, so whenever you set HttpResponse’s status code in a controller with
$response = $this->getResponse();$response->setStatusCode(404);
Loading a content via AJAX in a Bootstrap popover is a very common pattern and, although it is not supported out of the box by Bootstrap, it is very easy to get this functionality with jQuery.