Chunk not saved (Failed to save chunk)
- Platforms
- Paper · Purpur · single server
- Verified
- Verified
- Confidence
- Confidence 90%
What it looks like in the log
Any one of these lines is enough. The agent matches them locally, on your server.
logs/latest.log
[ERROR] Failed to save chunk
Symptoms
- After a restart, player changes in part of the world are rolled back
- In the log: “Failed to save chunk (x,z) in world '…'” and a stack trace
Cause
The server could not serialise or write the chunk data. Changes to this chunk since the last successful save may be lost.
Possible causes
- A disk problem: no space, no write permission, an I/O error (see Caused by)
- Invalid block entity/entity data (often after a plugin has meddled with it) breaks serialisation
- A server/fork bug
How to fixMedium risk
- Look at the exception in the evidence:
IOException/No space left on device/AccessDeniedException— a disk or permissions problem;NullPointerExceptionduring serialisation — corrupted chunk data. - For the disk: free up space (
df -h), check the owner and permissions of the world folder (the server must be able to write toworld/region). - For the data: use the chunk coordinates (x,z) to find the spot and check blocks that hold data (chests, spawners, plugin blocks); update the plugin that modifies them.
- Back up the world before restarting.
Translated from the Russian original; log lines are quoted verbatim.