DDoS attack came to Minecraft server. Is there a way to stop it?
Yes, use a firewall. How to do it? Completely depends on your setup and skill set. You could use something like F2B and UFW (heres a good guide Webdock : Configuring UFW and Fail2Ban to Mitigate Basic DDos Attacks ) if your on the linux. Windows built in firewall could do the job also if you messed with im sure but the kind of attack is needed to be known or anything someone suggests wont help really.
figure out the ranges your users come from and block everything else from jacking into your server. Nab yourself a copy of Wireshark and that will help you monitor the attacks. MS Advanced firewall is ok, just make rules on both sides blocking flow from all you don’t know ;).