WARNING: [UdpSessionHandler] Unable to find ClientConnection for null

  • Since restarting this morning, I keep getting spammed with "WARNING: [UdpSessionHandler] Unable to find ClientConnection for null" in server console. However I can connect to it fine, and it lists in the in game server list.

    This is the 1st time I see this. Any ideas? DDOS? Haapens every couple of seconds or so. Was happening all morning since restart (waited for everyone to log out).

    *Edit: Ok this seems to have cleared up on it's own, after one regular player joined after a few others. hmmmmmm

    "The past is history, the future a mystery, but today is a gift, which is why we call it the Present."

    Edited once, last by Juggernaut ().

  • It's back! :(

    I think I identified the source of this problem although not certain. I believe it may be related to the AutoLevel plugin I installed recently.
    If a regular player joins for the 1st time since the installation of AutoLevel, they get spammed every 3 seconds "your permissions have changed" until they RElog (at which point is fine). Server console gets spammed with: ...plugins\AutoLevels\database.db

    Some players ignore this message and continue playing.
    However, I notice if they don't log back in after playing, the server console continues to spam the message in my OP, even if I restart the server and no one is connected. Players connect and the warning continues. It seems to only clear when the player who originally created this 'loop' logs back in.

    I have many players connecting and overall the AutoLevel is working great and saving me a bunch of keystrokes not having to manually up rank players any more. :)

    @yahgiggle contact me anytime if you want any more info. TY for the plugin!

    "The past is history, the future a mystery, but today is a gift, which is why we call it the Present."

    Edited once, last by Juggernaut ().

  • Do you see this message on the server (i.e. in the server log) or in the client log? Basically the "Unable to find ClientConnection for ..." indicates that there was a message incoming from a client who isn't connected to the server. In this case the "UdpSessionHandler" sent this message, so it's about an UDP channel. It takes slightly longer to establish an UDP connection than a TCP connection, so if a player just connects to the server, but already receives messages while he isn't fully connected, this message occurs (or vice versa on the server - if the server receives a message from a client who isn't fully connected yet [or no longer connected to the server]).

    //Edit: I've checked the AutoLevel plugin. The problem is probably caused by the onPlayerSpawnEvent() method. It creates a new executor which does some database queries but also does some changes to the player gui and permissions every 60 seconds. If the player disconnects, the executor is still active and still has a reference to the old player object, trying to send messages to him.
    I'd recommend to add a player.isConnected() check to the runnable and also store the executor object as a player attribute. If the player disconnects (PlayerDisconnectEvent), retrieve the executor object and shut it down (so it no longer executes anything for offline players and also releases the resources - since in the current scenario, the executor nevers stops a new executor will be created every time a player connects)

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