Comment by leath
4 years ago
We've had several servers with OVH, including their kimisufi line, So You Start GAME line, their standard GAME line and their standard servers. While I'm sure these are great for common games their DDoS protection seems to get confused by our very non-standard protocol, ending up blocking most if not all traffic from non-connected players.
Might sound strange, but you could always contact @olesovhcom on Twitter. He is the CEO of OVH and he made change to their DDOS filter base on what we reported to him. He is always interested in improving is offering. But that was maybe 5 years ago, now maybe he will put you in contact with someone else, but back then they were actively looking for feedback to improve their filter.
Edit: you could always contact their support as well. Fighting DDOS on your own it's an expensive/difficult battle. But their DDOS filter is fully custom (mostly Asic and some Arbor as well).
A shot in the dark but maybe implement a wrapper for the protocol in something that looks more like http? Websockets perhaps? Otherwise I think you will have to build your own countermeasures specific to your protocol.
The blog post does mention this possibility. In a similar vein we can also try to mimic a protocol that is well supported by hosters, like source or minecraft but I'm fairly certain that would be the single most ugliest piece of code ever written :)