Something strange happens with my TCP port receives many connections

Discussion in 'Systems Administration' started by JuanDouCore_, Nov 20, 2019.

  1. It turns out that in recent days I realized that my 25565 / TCP port when receiving a large number of connections is beginning to reject / drop legitimate incoming connections as illegitimate randomly. In other words, once you can accept the connection but the other time you ping the port it rejects you.
    This happens exclusively when this port begins to receive a large number of connections. That is, there are times of the day where the ones you receive are not so many. And there he does not reject or drop the connection to anyone. But when I start receiving many connections, it begins to reject or drop all connections randomly (sometimes it does not sometimes).
    At one point I thought I had a problem with my system, so I proceeded to reinstall. After the reinstallation, I proceeded to install UFW but the same thing continues. In ufw I have it running with the rules it brings by default. I don't know if it's any Ubuntu firewall configuration or what.
    I would need help with this. Thank you
     
  2. I am very sorry that you are experiencing this. As this could be many causes, complications and such are you able to bring in a professional to inspect your machine's traffic to see what's really going on?
     
  3. Hello this could be some kind of attack
    Have you tried using tcpdump when the server is out of public?
    I recommend this plugin has a version of bungeecord patched which blocks any type of attack or crash or exploit
    https://www.spigotmc.org/resources/...ash-and-antibot-optimize-fps-and-tps-⭐.59866/