Minecraft Server Stuck at “Finished Unloading Ender Chest Data” During Shutdown? Here’s How to Troubleshoot

Are you experiencing issues with your Minecraft server getting stuck during shutdown, specifically after the log message “Finished Unloading Ender Chest Data”? You’re not alone. Many server administrators encounter this frustrating problem, which can lead to unclean shutdowns and potential data corruption, especially when using systemd services with timeouts.

This article delves into this specific Minecraft server shutdown hang, focusing on the “finished unloading ender chest data” message. We’ll analyze the problem, explore potential causes, and offer troubleshooting steps to help you resolve this issue and ensure your server shuts down smoothly every time.

From the provided server logs, we can see the shutdown process initiates correctly. Components like FTB Chunks and FTB Backups shut down as expected. The Ender Tanks and Ender Chests mods also appear to unload their data without immediate errors, as indicated by the “Finished Unloading EnderTank Data” and “Finished Unloading EnderChest Data” log entries.

However, the server doesn’t proceed with a clean shutdown after these messages. In the original user’s case, a significant delay occurs, followed by an unrelated java.io.IOError much later in the logs, likely triggered by a systemd timeout and forced termination. This suggests the server is hanging after the Ender Chest data unloading process, but not directly because of it throwing an error at that stage.

Here’s a snippet from the problematic server log:

[20May2022 10:26:01.056] [Server thread/INFO] [shetiphian.enderchests.EnderChests/]: Finished Unloading EnderChest Data
[20May2022 10:26:01.082] [Server thread/INFO] [net.minecraft.server.rcon.thread.GenericThread/]: Thread Query Listener stopped
[20May2022 10:26:59.970] [Server console handler/ERROR] [net.minecraft.server.dedicated.DedicatedServer/]: Caught previously unhandled exception : java.io.IOError: java.io.IOException: Error executing 'stty -a':

Possible Causes and Troubleshooting Steps:

1. Mod Conflicts or Interactions: While the logs indicate “Finished Unloading EnderChest Data,” there might be underlying issues with the Ender Chests mod or its interaction with other mods on your server.

   • Check Mod Versions: Ensure you are using the latest stable versions of Ender Chests and all other mods. Outdated or incompatible versions can cause unexpected behavior during server shutdown.
   • Test Without Ender Chests: As a troubleshooting step, try temporarily removing the Ender Chests mod to see if the shutdown issue persists. If the server shuts down cleanly without it, the mod is likely involved.
   • Investigate Mod Interactions: If removing Ender Chests isn’t feasible or doesn’t solve the problem, consider if there are any known conflicts between Ender Chests and other mods in your modpack (like ATM-7 in the original example). Mod compatibility lists or online forums for your modpack can be helpful.

2. Resource Intensive Shutdown Tasks: Even though the log says “Finished Unloading…”, there might be other resource-intensive tasks happening during the shutdown process that are taking longer than expected.

   • Monitor Server Resources: Use tools to monitor CPU, RAM, and disk I/O usage during server shutdown. High resource utilization could indicate a bottleneck causing the hang.
   • Optimize Server Performance: Ensure your server has sufficient resources and is properly optimized for your player load and modpack. Performance issues can exacerbate shutdown problems.

3. Systemd Service Configuration: If you are using systemd to manage your Minecraft server, the configuration might be contributing to the perceived hang.

   • Review Systemd Timeout: While a 60-second timeout should be sufficient for most clean shutdowns, consider if your specific server setup or modpack requires a longer grace period. You can adjust the TimeoutStopSec in your systemd service file.
   • Check Shutdown Script: If you are using a custom run.sh script for shutdown, review it for any potential delays or issues that could be causing the hang. Ensure the stop command is being sent correctly to the server.

4. Java Version or JVM Arguments: In rare cases, issues with the Java version or JVM arguments used to run your server could contribute to shutdown problems.

   • Update Java: Ensure you are using a recommended and stable version of Java for your Minecraft server version and modpack.
   • Review JVM Arguments: Check your JVM arguments for any potentially problematic settings. Consult Minecraft server optimization guides for recommended JVM arguments.

Moving Forward:

To effectively troubleshoot this “Minecraft Server Stuck At Finished Unloading Ender Chest Data” issue, systematically go through these steps. Start by investigating mod interactions, monitor server resources during shutdown, and carefully review your systemd service configuration if applicable. By methodically eliminating potential causes, you’ll be closer to identifying the root of the problem and achieving clean, reliable Minecraft server shutdowns.

If the issue persists, providing more detailed information about your server setup, modlist, and system configuration in online Minecraft server communities or mod-specific support channels can help you get more tailored assistance from experienced users and developers.