I am using VPS from OVH as a reverse proxy to protect my dedicated server from DDOS attacks. OVH has very good DDOS protection. My dedicated server hasn't.
Everything works good, I am attacking my VPS a lot via TCP attacks and OVH starts mitigating it very fast, my players (becouse I am running game server on dedicated) notice nothing.
The problem is when I attack my VPS via UDP attack. OVH starts mitigating it very fast too but my dedicated server start blocking connections from my VPS. I don't know why. But I read a lot about it and now I know that UFW (by default) blocking all INVALID packets.
I have a screenshot (from UFW logs in my dedi). As you can see, ufw block my VPS connections to 3306 port. I think these packets are invalid.
But why? The attack only was 60 second long. My dedi was blocking packets few hours! Why these packets were invalid?
