Help: No-one can connect to Tekkit Classic server

[ekimekim]

I'm running Tekkit 3.1.2. Nothing appears wrong in the logs, but no-one can connect (EndOfStream error).

I tried connecting with netcat (from both localhost and my home machine), the server waits for me to send something, then closes the connection when I do (this is consistent with normal behaviour). So it likely isn't a network problem.

When a player fails to connect, the log reads: "<ip>:<port> lost connection"

Server console is responsive, if a little laggy.

One thing I've noticed, one of the server threads seems to be pegging a core (the core is reporting 100% userland time and the relevant thread is at constant 100% usage).

The server has been running fine for almost a week, and suddenly stopped working.

I'm unsure exactly when, since we don't have players online 24/7.

My suspicion is that one of my players has created something in tekkit that is broken under multiplayer. When it loads the world anchors, the broken thing is loaded and causes an inf loop somewhere in the server code. I need help trying to work out what thing that is, any debugging techniques I could try, etc.

My setup:

Tekkit 3.1.2 with Nether Ores removed (it was causing a startup crash which I understand is a known issue).

Java version info:

java version "1.6.0_24"

OpenJDK Runtime Environment (IcedTea6 1.11.1) (6b24-1.11.1-4ubuntu2)

OpenJDK 64-Bit Server VM (build 20.0-b12, mixed mode)

Operating System is Ubuntu Precise (12.04) 64-bit, specific kernel version "3.2.0-23-virtual"

The hardware...isn't. It's a virtual machine with 4G of RAM, 4 VCPUs which report themselves as "Intel® Xeon® CPU X5650 @ 2.67GHz".

If it makes any difference, minecraft itself is running as a daemon which I start using start-stop-daemon's --background option. Its stdout and stderr are redirected to a file, and its stdin is redirected from a named pipe (which I can write to to type on the server console).

Server log dump (without FINE or FINEST as this exceeded message length limits):

182 recipes

27 achievements

22:23:26 [iNFO] Starting minecraft server version 1.2.5

22:23:26 [iNFO] Attempting early MinecraftForge initialization

22:23:26 [iNFO] Completed early MinecraftForge initialization

22:23:26 [iNFO] Forge Mod Loader version 2.2.91.173 for Minecraft 1.2.5 loading

22:23:26 [iNFO] Loading mods from /var/minecraft/mods

22:23:26 [iNFO] Directory weaponmod contained no mods

22:23:26 [iNFO] Forge Mod Loader has loaded 37 mods

22:23:26 [iNFO] MinecraftForge v3.3.8.152 Initialized

22:23:26 [iNFO] MinecraftForge v3.3.8.152 Initialized

22:23:26 [iNFO] [WeaponMod] Properties file read succesfully!

22:23:26 [WARNING] Configuration for mod_ComputerCraft.enableAPI_http found value 0 outside acceptable range 4.9E-324,1.7976931348623157E308

22:23:26 [iNFO] Loading ComputerCraft: To change block IDs, modify config/mod_ComputerCraft.cfg

22:23:26 [iNFO] ComputerCraft: computerBlockID 207

22:23:26 [iNFO] ComputerCraft: diskDriveBlockID 208

22:23:26 [iNFO] ComputerCraft: diskItemID 4000

22:23:26 [iNFO] CONFLICT @ -49 item slot already occupied by dan200.computer.shared.ItemComputer@2cf18e8e while adding net.minecraft.server.ItemBlock@26c623af

22:23:26 [iNFO] ComputerCraft: Searching for RedPowerLib...

22:23:26 [iNFO] ComputerCraft: RedPowerLib and methods located.

22:23:26 [iNFO] CONFLICT @ -48 item slot already occupied by dan200.computer.shared.ItemPeripheral@2cba5bdb while adding net.minecraft.server.ItemBlock@7ee49dcd

22:23:26 [iNFO] Initializing alchemy values for Equivalent Exchange..

22:23:26 [iNFO] Loading properties

22:23:26 [iNFO] Starting Minecraft server on *:25565

22:23:27 [iNFO] Loaded codechicken.wirelessredstone.core.CommandFreq

22:23:27 [iNFO] CONFLICT @ -78 item slot already occupied by net.minecraft.server.ItemBlock@5f1eb199 while adding codechicken.enderstorage.ItemEnderChest@581de498

22:23:27 [iNFO] CONFLICT @ -204 item slot already occupied by net.minecraft.server.ItemWithAuxData@edc86eb while adding net.minecraft.server.ItemMobSpawner@301db5ec

22:23:27 [iNFO] [iC2] Config loaded from /var/minecraft/./config/IC2.cfg

22:23:28 [iNFO] RedPowerCore: MinecraftForge minor version mismatch, expecting 3.1.x, may lead to unexpected behavior

22:23:28 [iNFO] Starting BuildCraft 2.2.14

22:23:28 [iNFO] Copyright © SpaceToad, 2011

22:23:28 [iNFO] http://www.mod-buildcraft.com

22:23:28 [iNFO] CONFLICT @ 1237 item slot already occupied by ccSensors.shared.ItemWiFiTransmitter@546d3b92 while adding ccSensors.shared.ItemWiFiTransmitter@4f62198b

22:23:28 [iNFO] CONFLICT @ -41 item slot already occupied by ccSensors.shared.ItemComputerSensorBlock@50fa70a4 while adding net.minecraft.server.ItemBlock@69f94884

22:23:28 [iNFO] [ccSensors] INFO: Loading SensorModule: Buildcraft

22:23:28 [iNFO] [ccSensors] INFO: Loading SensorModule: IndustrialCraft2

22:23:28 [iNFO] [ccSensors] INFO: Loading SensorModule: Forestry

22:23:28 [iNFO] [ccSensors] INFO: mod_Forestry not found - SensorModule is disabled.

22:23:28 [iNFO] [ccSensors] INFO: Loading SensorModule: RedPower2

22:23:28 [iNFO] [ccSensors] INFO: Loading SensorModule: EquivalentExchange

22:23:28 [iNFO] [ccSensors] INFO: Loading SensorModule: APS

22:23:28 [iNFO] [ccSensors] INFO: mod_BuildcraftAPS not found - SensorModule is disabled.

22:23:28 [iNFO] [ccSensors] INFO: Loading SensorModule: APS

22:23:28 [iNFO] [ccSensors] INFO: mod_ThaumCraft not found - SensorModule is disabled.

22:23:28 [iNFO] CompactSolars: MinecraftForge minor version mismatch, expecting 3.2.x, may lead to unexpected behavior

22:23:28 [iNFO] ComputerCraft: turtleBlockID 216

22:23:28 [iNFO] CONFLICT @ -40 item slot already occupied by dan200.turtle.shared.ItemTurtle@37ed1dbe while adding net.minecraft.server.ItemBlock@303bc1a1

22:23:28 [iNFO] [iC2] Loading IC2 submodule: bcIntegration22x

22:23:28 [iNFO] [iC2] BuildCraft integration module loaded

22:23:28 [iNFO] [iC2] Loaded minor compatibility modules: none

22:23:28 [iNFO] Forge Mod Loader load complete, 37 mods loaded

22:23:28 [iNFO] This server is running CraftBukkit version git-Bukkit-jenkins-CraftBukkit-173 (MC: 1.2.5) (Implementing API version 1.2.5-R4.1-MCPC-SNAPSHOT)

22:23:29 [iNFO] Loading mod_WirelessRedstoneAddons vForgeMod

22:23:29 [iNFO] Loading mod_IronChest vForgeMod

22:23:29 [iNFO] Loading mod_IC2_ChargingBench vForgeMod

22:23:29 [iNFO] Loading mod_BuildCraftEnergy vForgeMod

22:23:29 [iNFO] Loading mod_RedPowerWiring vForgeMod

22:23:29 [iNFO] Loading mod_MinecraftForge vForgeMod

22:23:29 [iNFO] Loading mod_RedPowerControl vForgeMod

22:23:29 [iNFO] Loading mod_BuildCraftCore vForgeMod

22:23:29 [iNFO] Loading mod_ImmibisCore vForgeMod

22:23:29 [iNFO] Loading mod_BuildCraftFactory vForgeMod

22:23:29 [iNFO] Loading mod_IC2 vForgeMod

22:23:29 [iNFO] Loading mod_BuildCraftBuilders vForgeMod

22:23:29 [iNFO] Loading mod_RedPowerMachine vForgeMod

22:23:29 [iNFO] Loading mod_RedPowerLighting vForgeMod

22:23:29 [iNFO] Loading mod_RedPowerWorld vForgeMod

22:23:29 [iNFO] Loading mod_ComputerCraft vForgeMod

22:23:29 [iNFO] Loading mod_EE vForgeMod

22:23:29 [iNFO] Loading mod_TubeStuff vForgeMod

22:23:29 [iNFO] Loading mod_BuildCraftTransport vForgeMod

22:23:29 [iNFO] Loading mod_NotEnoughItems vForgeMod

22:23:29 [iNFO] Loading mod_PowerConverters vForgeMod

22:23:29 [iNFO] Loading mod_AdditionalPipes vForgeMod

22:23:29 [iNFO] Loading mod_CCTurtle vForgeMod

22:23:29 [iNFO] Loading mod_Railcraft vForgeMod

22:23:29 [iNFO] Loading mod_IC2AdvancedMachines vForgeMod

22:23:29 [iNFO] Loading mod_RedPowerCore vForgeMod

22:23:29 [iNFO] Loading mod_RedPowerLogic vForgeMod

22:23:29 [iNFO] Loading mod_IC2NuclearControl vForgeMod

22:23:29 [iNFO] Loading mod_WirelessRedstoneRedPower vForgeMod

22:23:29 [iNFO] Loading mod_ModularForceFieldSystem vForgeMod

22:23:29 [iNFO] Loading mod_ImmiChunkLoaders vForgeMod

22:23:29 [iNFO] Loading mod_ccSensors vForgeMod

22:23:29 [iNFO] Loading mod_CompactSolars vForgeMod

22:23:29 [iNFO] Loading mod_EnderStorage vForgeMod

22:23:29 [iNFO] Loading Balkon's WeaponMod vForgeMod

22:23:29 [iNFO] Loading mod_CodeChickenCore vForgeMod

22:23:29 [iNFO] Loading mod_WirelessRedstoneCore vForgeMod

22:23:29 [iNFO] Preparing level "world"

22:23:29 [iNFO] Default game type: 0

22:23:29 [iNFO] Registering world world, dimension 0, of providertype net.minecraft.server.WorldProviderNormal@55291cd(0) with Minecraft Forge

22:23:29 [iNFO] Registering world world_the_end, dimension 1, of providertype net.minecraft.server.WorldProviderTheEnd@d44752d(0) with Minecraft Forge

22:23:29 [iNFO] Registering world world_nether, dimension -1, of providertype net.minecraft.server.WorldProviderHell@3a2cd728(0) with Minecraft Forge

22:23:29 [iNFO] Preparing start region for level 0 (Seed: 4197205139005985982)

22:23:30 [iNFO] Preparing start region for level 1 (Seed: 4197205139005985982)

22:23:30 [WARNING] Could not get information about this CraftBukkit version; perhaps you are running a custom one?: FileNotFoundException

22:23:30 [iNFO] Preparing spawn area: 0%

22:23:30 [iNFO] Preparing start region for level 2 (Seed: 4197205139005985982)

22:23:31 [iNFO] Preparing spawn area: 97%

22:23:31 [iNFO] Server permissions file permissions.yml is empty, ignoring it

22:23:31 [iNFO] Done (2.836s)! For help, type "help" or "?"

22:23:33 [iNFO] [Railcraft] Loaded 2 saved Anchors