Nothing can be DDoS proof in 100%. And I wouldn't call blocking access to the server as "hacking". 
If I have more time - I'd like to take one (around 20 slot would be enough) - but I don't have time right now, too bad for me, huh?  
Yeah, I know.. But it will protect the "noobiest" ddos attacks, also it can't be hacked, there isn't anything that is installed as root..    Yeah, ask me if you need a server. 
Your root account is not 100% secured, even the kernel can have leaks etc..