Server Log

The server log gives you insight into what is happening inside 3DPrintForge — useful for troubleshooting, monitoring, and diagnostics.

Go to: https://localhost:3443/#logs

Real-time view

The log stream updates in real time via WebSocket:

1. Go to System → Server Log
2. New log lines appear automatically at the bottom
3. Click Lock bottom to always scroll to the latest log
4. Click Freeze to stop auto-scrolling and read existing lines

The default view shows the last 500 log lines.

Log levels

Each log line has a level:

Level	Color	Description
ERROR	Red	Errors that affect functionality
WARN	Orange	Warnings — something may go wrong
INFO	Blue	Normal operational information
DEBUG	Gray	Detailed developer information

Log level configuration

Change log level under Settings → System → Log level. For normal operation, use INFO. Use DEBUG only for troubleshooting as it generates much more data.

Filtering

Use the filter toolbar at the top of the log view:

1. Log level — show only ERROR / WARN / INFO / DEBUG or a combination
2. Module — filter by system module:
   • mqtt — MQTT communication with printers
   • api — API requests
   • db — database operations
   • auth — authentication events
   • queue — print queue events
   • guard — Print Guard events
   • backup — backup operations
3. Free text — search log text (supports regex)
4. Timestamp — filter by date range

Combine filters for precise troubleshooting.

Common error situations

MQTT connection issues

Look for log lines from the mqtt module:

ERROR [mqtt] Connection to printer XXXX failed: Connection refused

Solution: Check that the printer is on, the access key is correct, and the network is working.

Database errors

ERROR [db] Migration v95 failed: SQLITE_CONSTRAINT

Solution: Take a backup and run database repair via Settings → System → Repair database.

Authentication errors

WARN [auth] Failed login for user admin from IP 192.168.1.x

Many failed logins may indicate a brute-force attempt. Check whether IP whitelisting should be enabled.

Exporting logs

1. Click Export log
2. Select time period (default: last 24 hours)
3. Choose format: TXT (human-readable) or JSON (machine-readable)
4. The file is downloaded

Exported logs are useful when reporting bugs or contacting support.

Log rotation

Logs are rotated automatically:

Setting	Default
Max log file size	50 MB
Number of rotated files to keep	5
Total max log size	250 MB

Adjust under Settings → System → Log rotation. Older log files are automatically compressed with gzip.

Log file location

Log files are stored on the server:

./data/logs/
├── 3dprintforge.log          (active log)
├── 3dprintforge.log.1.gz     (rotated)
├── 3dprintforge.log.2.gz     (rotated)
└── ...

SSH access

To read logs directly on the server via SSH:

tail -f ./data/logs/3dprintforge.log