I would think that the post you respond to either supposes a hosted service (you do not control the server and its iptables) or that it multiple layers of prote

I would think that the post you respond to either supposes a hosted service (you do not control the server and its iptables) or that it multiple layers of protection is good for something critical. But yes, if it's your own server, everyone should remember that regular Linux features are darn powerful, too.