Just to do justice to my coworkers working on the ALOHA appliance, it's not just a "server with haproxy preinstalled" but a tight integration of haproxy plus a few management tools into a dedicated distro built from scratch and packaged as an upgradable image like you'd have on your routers or switches. The whole OS image is around 16 megabytes, kernel included, and it contains a 10 Gbps-capable anti-ddos module, a web interface, and troubleshooting tools. And of course you have root access on it and it doesn't void your support to start to hack on it (not pointing the finger at anyone, but still a little bit :-))