Factorio: Reading Server Logs
The Factorio log file is the "black box" of your dedicated server. Whether you are troubleshooting a startup crash, a mod version mismatch, or the dreaded Desync Loop, the factorio-current.log holds the key to the solution.
1. The File Location
The active log is always named factorio-current.log. When the server restarts, this file is renamed to factorio-previous.log automatically.
2. Startup Sequence
The first 50 lines of the log show the "Mod Loading" phase. If the server crashes instantly, look here first for "Failed to load mod" errors.
3. Desync Reports
If a "Desync" occurs, the log will generate a path to a specific "Desync Report" zip file. This is crucial for developers to fix underlying engine or mod bugs.
How to Access the Log
- Navigate to the Supercraft File Manager.
- The file is usually located in the root directory.
- Click Edit or View on
factorio-current.logto read it directly in your browser.
Common Error Messages
| Log Message | Recommended Fix |
|---|---|
Mod mismatch: Player has X, Server has Y |
The player must sync their mods. Advise them to use the "Sync Mods with Server" button when joining. |
Address already in use |
Port 34197 is blocked. The server process may still be running in the background. Restart the server. |
No such file or directory |
The server tried to load a save file (configured in server-settings.json) that doesn't exist. Check your save name. |
Refusing to start with version X |
The map file was saved in a newer version of Factorio (e.g., 2.0). You must update the server to match. |
Expert Tip: When sharing a log for support, use a service like Pastebin and share the link. Be aware that logs can contain sensitive information like server IP addresses.
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