Uncaught exception with Fabric Loader

[Frankenberrypi]

This is likely user error since it's my first time trying this. I'm able to get a server running just fine with vanilla, but get errors when trying to use Fabric. My ultimate goal is to run mods to support the Hermitcraft S9 map download, but currently I'm just trying to get Fabric running on its own.

It looks like the error in question is:

[FabricLoader/]: Uncaught exception in thread "main"

Docker compose file

version: "3.8"

services:
  hermitcraft9:
    image: itzg/minecraft-server
    tty: true
    restart: always
    stdin_open: true
    ports:
      - 25565:25565
    environment:
      EULA: TRUE
      VERSION: 1.20.1
      TYPE: FABRIC
    volumes:
      # attach the relative directory 'data' to the container's /data path
      - /mnt/network_storage/Minecraft_Worlds_Java/hc_tester:/data

Logs

[init] Changing ownership of /data to 1000 ...

[init] Running as uid=1000 gid=1000 with /data as 'drwxrwxrwx 2 0 0 0 Dec 30 16:14 /data'

[init] Resolving type given FABRIC

[mc-image-helper] 16:14:04.291 INFO  : Downloaded ./fabric-server-mc.1.20.1-loader.0.15.3-launcher.0.11.2.jar

[init] Creating server properties in /data/server.properties

[init] Disabling whitelist functionality

[mc-image-helper] 16:14:06.693 INFO  : Created/updated 4 properties in /data/server.properties

[init] Setting initial memory to 1G and max to 1G

[init] Starting the Minecraft server...

Downloading Minecraft server

Installing Fabric Loader 0.15.3(1.20.1) on the server

Downloading required files

Downloading library org.ow2.asm:asm:9.6

Downloading library org.ow2.asm:asm-analysis:9.6

Downloading library org.ow2.asm:asm-commons:9.6

Downloading library org.ow2.asm:asm-tree:9.6

Downloading library org.ow2.asm:asm-util:9.6

Downloading library net.fabricmc:sponge-mixin:0.12.5+mixin.0.8.5

Downloading library net.fabricmc:intermediary:1.20.1

Downloading library net.fabricmc:fabric-loader:0.15.3

Generating server launch JAR

Unpacking 1.20.1/server-1.20.1.jar (versions:1.20.1) to versions/1.20.1/server-1.20.1.jar

Unpacking com/github/oshi/oshi-core/6.2.2/oshi-core-6.2.2.jar (libraries:com.github.oshi:oshi-core:6.2.2) to libraries/com/github/oshi/oshi-core/6.2.2/oshi-core-6.2.2.jar

Unpacking com/google/code/gson/gson/2.10/gson-2.10.jar (libraries:com.google.code.gson:gson:2.10) to libraries/com/google/code/gson/gson/2.10/gson-2.10.jar

Unpacking com/google/guava/failureaccess/1.0.1/failureaccess-1.0.1.jar (libraries:com.google.guava:failureaccess:1.0.1) to libraries/com/google/guava/failureaccess/1.0.1/failureaccess-1.0.1.jar

Unpacking com/google/guava/guava/31.1-jre/guava-31.1-jre.jar (libraries:com.google.guava:guava:31.1-jre) to libraries/com/google/guava/guava/31.1-jre/guava-31.1-jre.jar

Unpacking com/mojang/authlib/4.0.43/authlib-4.0.43.jar (libraries:com.mojang:authlib:4.0.43) to libraries/com/mojang/authlib/4.0.43/authlib-4.0.43.jar

Unpacking com/mojang/brigadier/1.1.8/brigadier-1.1.8.jar (libraries:com.mojang:brigadier:1.1.8) to libraries/com/mojang/brigadier/1.1.8/brigadier-1.1.8.jar

Unpacking com/mojang/datafixerupper/6.0.8/datafixerupper-6.0.8.jar (libraries:com.mojang:datafixerupper:6.0.8) to libraries/com/mojang/datafixerupper/6.0.8/datafixerupper-6.0.8.jar

Unpacking com/mojang/logging/1.1.1/logging-1.1.1.jar (libraries:com.mojang:logging:1.1.1) to libraries/com/mojang/logging/1.1.1/logging-1.1.1.jar

Unpacking commons-io/commons-io/2.11.0/commons-io-2.11.0.jar (libraries:commons-io:commons-io:2.11.0) to libraries/commons-io/commons-io/2.11.0/commons-io-2.11.0.jar

Unpacking io/netty/netty-buffer/4.1.82.Final/netty-buffer-4.1.82.Final.jar (libraries:io.netty:netty-buffer:4.1.82.Final) to libraries/io/netty/netty-buffer/4.1.82.Final/netty-buffer-4.1.82.Final.jar

Unpacking io/netty/netty-codec/4.1.82.Final/netty-codec-4.1.82.Final.jar (libraries:io.netty:netty-codec:4.1.82.Final) to libraries/io/netty/netty-codec/4.1.82.Final/netty-codec-4.1.82.Final.jar

Unpacking io/netty/netty-common/4.1.82.Final/netty-common-4.1.82.Final.jar (libraries:io.netty:netty-common:4.1.82.Final) to libraries/io/netty/netty-common/4.1.82.Final/netty-common-4.1.82.Final.jar

Unpacking io/netty/netty-handler/4.1.82.Final/netty-handler-4.1.82.Final.jar (libraries:io.netty:netty-handler:4.1.82.Final) to libraries/io/netty/netty-handler/4.1.82.Final/netty-handler-4.1.82.Final.jar

Unpacking io/netty/netty-resolver/4.1.82.Final/netty-resolver-4.1.82.Final.jar (libraries:io.netty:netty-resolver:4.1.82.Final) to libraries/io/netty/netty-resolver/4.1.82.Final/netty-resolver-4.1.82.Final.jar

Unpacking io/netty/netty-transport/4.1.82.Final/netty-transport-4.1.82.Final.jar (libraries:io.netty:netty-transport:4.1.82.Final) to libraries/io/netty/netty-transport/4.1.82.Final/netty-transport-4.1.82.Final.jar

Unpacking io/netty/netty-transport-classes-epoll/4.1.82.Final/netty-transport-classes-epoll-4.1.82.Final.jar (libraries:io.netty:netty-transport-classes-epoll:4.1.82.Final) to libraries/io/netty/netty-transport-classes-epoll/4.1.82.Final/netty-transport-classes-epoll-4.1.82.Final.jar

Unpacking io/netty/netty-transport-native-epoll/4.1.82.Final/netty-transport-native-epoll-4.1.82.Final-linux-x86_64.jar (libraries:io.netty:netty-transport-native-epoll:4.1.82.Final:linux-x86_64) to libraries/io/netty/netty-transport-native-epoll/4.1.82.Final/netty-transport-native-epoll-4.1.82.Final-linux-x86_64.jar

Unpacking io/netty/netty-transport-native-epoll/4.1.82.Final/netty-transport-native-epoll-4.1.82.Final-linux-aarch_64.jar (libraries:io.netty:netty-transport-native-epoll:4.1.82.Final:linux-aarch_64) to libraries/io/netty/netty-transport-native-epoll/4.1.82.Final/netty-transport-native-epoll-4.1.82.Final-linux-aarch_64.jar

Unpacking io/netty/netty-transport-native-unix-common/4.1.82.Final/netty-transport-native-unix-common-4.1.82.Final.jar (libraries:io.netty:netty-transport-native-unix-common:4.1.82.Final) to libraries/io/netty/netty-transport-native-unix-common/4.1.82.Final/netty-transport-native-unix-common-4.1.82.Final.jar

Unpacking it/unimi/dsi/fastutil/8.5.9/fastutil-8.5.9.jar (libraries:it.unimi.dsi:fastutil:8.5.9) to libraries/it/unimi/dsi/fastutil/8.5.9/fastutil-8.5.9.jar

Unpacking net/java/dev/jna/jna/5.12.1/jna-5.12.1.jar (libraries:net.java.dev.jna:jna:5.12.1) to libraries/net/java/dev/jna/jna/5.12.1/jna-5.12.1.jar

Unpacking net/java/dev/jna/jna-platform/5.12.1/jna-platform-5.12.1.jar (libraries:net.java.dev.jna:jna-platform:5.12.1) to libraries/net/java/dev/jna/jna-platform/5.12.1/jna-platform-5.12.1.jar

Unpacking net/sf/jopt-simple/jopt-simple/5.0.4/jopt-simple-5.0.4.jar (libraries:net.sf.jopt-simple:jopt-simple:5.0.4) to libraries/net/sf/jopt-simple/jopt-simple/5.0.4/jopt-simple-5.0.4.jar

Unpacking org/apache/commons/commons-lang3/3.12.0/commons-lang3-3.12.0.jar (libraries:org.apache.commons:commons-lang3:3.12.0) to libraries/org/apache/commons/commons-lang3/3.12.0/commons-lang3-3.12.0.jar

Unpacking org/apache/logging/log4j/log4j-api/2.19.0/log4j-api-2.19.0.jar (libraries:org.apache.logging.log4j:log4j-api:2.19.0) to libraries/org/apache/logging/log4j/log4j-api/2.19.0/log4j-api-2.19.0.jar

Unpacking org/apache/logging/log4j/log4j-core/2.19.0/log4j-core-2.19.0.jar (libraries:org.apache.logging.log4j:log4j-core:2.19.0) to libraries/org/apache/logging/log4j/log4j-core/2.19.0/log4j-core-2.19.0.jar

Unpacking org/apache/logging/log4j/log4j-slf4j2-impl/2.19.0/log4j-slf4j2-impl-2.19.0.jar (libraries:org.apache.logging.log4j:log4j-slf4j2-impl:2.19.0) to libraries/org/apache/logging/log4j/log4j-slf4j2-impl/2.19.0/log4j-slf4j2-impl-2.19.0.jar

Unpacking org/joml/joml/1.10.5/joml-1.10.5.jar (libraries:org.joml:joml:1.10.5) to libraries/org/joml/joml/1.10.5/joml-1.10.5.jar

Unpacking org/slf4j/slf4j-api/2.0.1/slf4j-api-2.0.1.jar (libraries:org.slf4j:slf4j-api:2.0.1) to libraries/org/slf4j/slf4j-api/2.0.1/slf4j-api-2.0.1.jar

Starting net.fabricmc.loader.impl.game.minecraft.BundlerClassPathCapture

[16:14:21] [INFO] [FabricLoader/GameProvider]: Loading Minecraft 1.20.1 with Fabric Loader 0.15.3

[16:14:22] [INFO] [FabricLoader/GameRemap]: Fabric is preparing JARs on first launch, this may take a few seconds...

[16:14:24] [ERROR] [FabricLoader/]: Uncaught exception in thread "main"

java.lang.RuntimeException: An exception occurred when launching the server!

	at net.fabricmc.loader.impl.launch.server.FabricServerLauncher.main(FabricServerLauncher.java:71)

	at net.fabricmc.installer.ServerLauncher.main(ServerLauncher.java:69)

Caused by: java.lang.RuntimeException: error remapping game jars [/data/versions/1.20.1/server-1.20.1.jar]

	at net.fabricmc.loader.impl.game.GameProviderHelper.deobfuscate(GameProviderHelper.java:244)

	at net.fabricmc.loader.impl.game.minecraft.MinecraftGameProvider.initialize(MinecraftGameProvider.java:321)

	at net.fabricmc.loader.impl.launch.knot.Knot.init(Knot.java:140)

	at net.fabricmc.loader.impl.launch.knot.Knot.launch(Knot.java:68)

	at net.fabricmc.loader.impl.launch.knot.KnotServer.main(KnotServer.java:23)

	at net.fabricmc.loader.impl.launch.server.FabricServerLauncher.main(FabricServerLauncher.java:69)

	... 1 more

Caused by: java.nio.file.FileSystemException: /data/./.fabric/remappedJars/minecraft-1.20.1-0.15.3/zipfstmp12607438164232900423.tmp: Operation not permitted

	at java.base/sun.nio.fs.UnixException.translateToIOException(Unknown Source)

	at java.base/sun.nio.fs.UnixException.rethrowAsIOException(Unknown Source)

	at java.base/sun.nio.fs.UnixException.rethrowAsIOException(Unknown Source)

	at java.base/sun.nio.fs.UnixFileAttributeViews$Posix.setMode(Unknown Source)

	at java.base/sun.nio.fs.UnixFileAttributeViews$Posix.setPermissions(Unknown Source)

	at java.base/java.nio.file.Files.setPosixFilePermissions(Unknown Source)

	at jdk.zipfs/jdk.nio.zipfs.ZipFileSystem.sync(Unknown Source)

	at jdk.zipfs/jdk.nio.zipfs.ZipFileSystem.lambda$close$9(Unknown Source)

	at java.base/java.security.AccessController.doPrivileged(Unknown Source)

	at jdk.zipfs/jdk.nio.zipfs.ZipFileSystem.close(Unknown Source)

	at net.fabricmc.loader.impl.lib.tinyremapper.OutputConsumerPath.close(OutputConsumerPath.java:226)

	at net.fabricmc.loader.impl.game.GameProviderHelper.deobfuscate0(GameProviderHelper.java:314)

	at net.fabricmc.loader.impl.game.GameProviderHelper.deobfuscate(GameProviderHelper.java:242)

	... 6 more

[itzg]

Sounds like you might have file ownership/permission mismatch in your /mnt/network_storage/Minecraft_Worlds_Java/hc_tester directory. The container will run the Minecraft process with uid 1000.

[itzg]

It all runs within the same process. It sounds like a particular mod in the failing modpack is perhaps the problem.

[paulwrath1223]

Thanks for the response. I ended up just using a different pack

[paulwrath1223]

So it turns out I ran into the problem again and found this thread looking up the problem. I can now confirm that it won't load Fabric by itself with no mods. I have given full permission to UID (and GUID) 568 which is what the container runs as in truenas, as well as UID 1000 which you mentioned is what the container assigns minecraft to.

[paulwrath1223]

Here are the permissions for the exact file that was failed to read:

The logs also seem to indicate that it is trying to set new permissions (at java.base/sun.nio.fs.UnixFileAttributeViews$Posix.setPermissions(Unknown Source))

ls -l of the offending file from the container shell: -rwxrwxrwx 1 minecraft minecraft 15453058 Aug 10 16:21 zipfstmp10884944103339798190.tmp

[Paul-Preteau]

Did you find a solution? I am running into the same issue.