This happen in ALL games, not just with CS2D. So, if you want to host a server, you must be prepared to handle with this. In my case, I've rent a VPS with anti-ddos, I made some extra protection by myself and an auto-restart for the dedicated server in case of a crash for any reason. Even with all that, It's not 100% safe.

Paying for anti-ddos is pointless IMO, if someone wants to crash your server it won't take too much effort.

You're just wasting money, you'd be better off buying a stronger server.

Buying a stronger server costs more.. EG:. Check OVH or something and see what a good server cost.. Not for CS2D, it's not worth it. Sadly.

@ Marcell: A few things.

It's not sad that you don't need a powerful server for CS2D, that is an awesome thing that allows us to spend around 1 EUR a month and host like 7 servers.
Buying a stronger server (usually) costs as much as DDoS protection, but it does way more (IMO), thus it is worth it (depending on your situation).

The thing that isn't worth it, is spending money on DDoS protection or a stronger server rather than just having a script that restarts your servers. *

* If your sole purpose is to prevent crashes, that is because CS2D is way too easy to crash, even without DDoS.

You didn't get me right, I was meaning, buying a GOOD server with DDoS protection is sad... It's not worth at all. By a good server I meant at least $100 which covers DDoS and gives you a nice server.

tl;dr

Either spend a shit ton of money or just deal with it.