Troubleshooting Crash Reports: A Beginner's Guide to Reading Minecraft Logs
Nothing in server administration is more intimidating than a 200-line crash report. But after reading a few hundred of them, a pattern emerges: almost every Minecraft crash falls into one of five categories, and each category has a tell-tale signature you can spot in 30 seconds.
Where to Find Crash Logs
Logs are stored in /logs/latest.log. Crash reports appear in /crash-reports/ with timestamps in the filename.
In the Space-Node panel, logs are accessible directly from the server console. Copy the last 100 lines when seeking support.
The Five Crash Signatures
1. Out of Memory
java.lang.OutOfMemoryError: Java heap space
Fix: Increase -Xmx in your JVM arguments. If you are already at 12 GB and still crashing, a memory leak in a plugin is the culprit. Bisect-test by removing plugins half at a time.
2. Missing/Incompatible Mod or Plugin
java.lang.ClassNotFoundException: com.example.SomePluginClass
Fix: A plugin is looking for a class that doesn't exist — either a dependency isn't installed, or you have a version mismatch between plugin and server version. Check all plugin dependencies.
3. Corrupted World Data
java.io.IOException: Error reading region file
Fix: A region file (.mca) is corrupted. Use MCEdit or Amulet to identify and remove the broken region. Restore from backup if corruption is widespread.
4. Thread Deadlock (Watchdog)
A single server tick took 60.00 seconds
Caused by: java.lang.StackOverflowError
Fix: A plugin or mod entered an infinite loop. Enable Spark profiler before reproducing the crash to identify which plugin is causing the stack overflow.
5. Version Mismatch
This server requires Minecraft X.X.X (not X.X.Y)
Fix: Your server jar version doesn't match your client version, or a plugin was compiled for a different server API version. Update either the server jar or the incompatible plugin.
The Bisect Method for Unknown Crashes
When you cannot identify the cause from the log alone:
- Remove half your plugins
- Start the server
- Reproduce the crash condition
- If crash is gone: the culprit was in the removed half. Re-add and repeat.
- If crash persists: culprit is in the remaining half. Remove and repeat.
This binary search converges to the problematic plugin in 4–6 restart cycles regardless of how many plugins you have.
Using Paste Sites for Support
When asking for help (on Discord, forums, or Space-Node support chat), paste your full log using paste.gg or [pastebin.com]. Never post raw crash text in a chat — it is unreadable and unhelpful. A paste link is searchable and shareable.