1. Guest, as per the stickied thread, this forum has not been in use since 2014. All bugs and feature requests should be posted to JIRA.

Crash "Failed to check session lock, aborting"

Discussion in 'Bugs & Feature Requests' started by MinecraftAdmin, Apr 14, 2013.

  1. My server has been disappearing from client multiplayer server lists despite being online for connected players.


    This is what the disconnected players see despite already connected players being on the server and playing. This error is followed by this repeating unit of spam in the console.

    2013-04-14 08:12:50 [SEVERE] net.minecraft.server.v1_5_R2.ExceptionWorldConflict: Failed to check session lock, aborting
    2013-04-14 08:12:50 [SEVERE] at net.minecraft.server.v1_5_R2.WorldNBTStorage.checkSession(WorldNBTStorage.java:75)
    2013-04-14 08:12:50 [SEVERE] at net.minecraft.server.v1_5_R2.World.E(World.java:2714)
    2013-04-14 08:12:50 [SEVERE] at net.minecraft.server.v1_5_R2.ChunkRegionLoader.a(ChunkRegionLoader.java:118)
    2013-04-14 08:12:50 [SEVERE] at net.minecraft.server.v1_5_R2.ChunkProviderServer.saveChunk(ChunkProviderServer.java:209)
    2013-04-14 08:12:50 [SEVERE] at net.minecraft.server.v1_5_R2.ChunkProviderServer.unloadChunks(ChunkProviderServer.java:299)
    2013-04-14 08:12:50 [SEVERE] at net.minecraft.server.v1_5_R2.WorldServer.doTick(WorldServer.java:196)
    2013-04-14 08:12:50 [SEVERE] at net.minecraft.server.v1_5_R2.MinecraftServer.r(MinecraftServer.java:553)
    2013-04-14 08:12:50 [SEVERE] at net.minecraft.server.v1_5_R2.DedicatedServer.r(DedicatedServer.java:229)
    2013-04-14 08:12:50 [SEVERE] at net.minecraft.server.v1_5_R2.MinecraftServer.q(MinecraftServer.java:471)
    2013-04-14 08:12:50 [SEVERE] at net.minecraft.server.v1_5_R2.MinecraftServer.run(MinecraftServer.java:403)
    2013-04-14 08:12:50 [SEVERE] at net.minecraft.server.v1_5_R2.ThreadServerApplication.run(SourceFile:573)
    The complete error log is here.

    I have already tried deleting the session lock file in my main world folder multiple times, but this error pops up every few hours, and the server has to be restarted to allow players to connect again.
    #1 MinecraftAdmin, Apr 14, 2013
    Last edited: Apr 14, 2013
  2. Jigsaw


    What is with the HawkEye error? Does it do that everytime?
    • Useful Useful x 1
  3. That pops pops up over a few dozen times every minute. Not sure if related to the session lock issue.
  4. Jigsaw


    I'm not sure if it is related either. The only time I have ever seen the "Failed to check session lock, aborting" message is when there were too many files open and the OS could no longer open the session lock file to check it. I would definitely look into the HawkEye error and see if I can get that resolved.
    • Winner Winner x 1
  5. You know what, that's probably it. Approximately 1/4 times this error occurs, the server runs out of memory and crashes itself. It could just be too many open files without it reading the error. I suspect MCMMO again. Might have to delete all MCMMO regions.
  6. You were right, I deleted all the MCMMO region files, restarted the server, and am no longer experiencing the issue. Thanks a million!
    • Like Like x 1
  7. Bestle


    • Winner Winner x 1
  8. Jigsaw


    I have mine set to 65,536. It was defaulted to 1,024.
  9. Do you think a cronjob on the server box that dumps the entire servers mysql database into an sql file could cause a lot of files to open?
  10. Jigsaw


    I highly doubt that. What commands/script is your cron job running? I would guess that this is a plugin causing this over anything else.
  11. The error appeared a few hours after a massive 60 second server lag spike daily at exactly 12:00am, which after further inspection turned out to be a MySQL backup cron job that ran on the server regularly, which is why I assumed a connection.