Printer Connection Issues

Printer Connection Issues

Troubleshoot printer connections by following the request path from Printbuddy to the printer.

1. Confirm provider type

Use the correct provider:

• Bambu Lab for Bambu local access.
• Klipper, Fluidd, or Mainsail for Moonraker.
• PrusaLink for local PrusaLink.
• Prusa Connect for cloud/mobile API.

2. Test from the Printbuddy host

Moonraker example:

curl -v http://<printer-ip>:7125/server/info

PrusaLink example:

curl -v http://<printer-ip>/api/v1/status

For modern PrusaLink printers using Digest authentication, a plain unauthenticated curl may return 401 Unauthorized; that still proves the endpoint is reachable. Use Printbuddy's Test Connection flow with the stored credentials to verify the real auth mode.

Camera example:

curl -I '<camera-url>'

3. Check credentials

Redact credentials, but verify:

• Bambu access code and serial number.
• Moonraker token if enabled.
• PrusaLink credentials/secret.
• Prusa Connect token.

4. Check logs

docker compose logs --tail=200 printbuddy

Look for HTTP status codes, refused connections, DNS failures, and timeout errors.

PrusaLink / CORE One upload issues

PrusaLink/Core One uploads write ready-to-print .gcode or .bgcode files to the printer's USB storage. Large files can take a few seconds to a few minutes while the printer writes the file.

Useful checks:

• Confirm the printer is configured as PrusaLink, not Moonraker/Fluidd/Mainsail.
• Confirm the API URL is the local PrusaLink URL, usually http://<printer-ip>/ or the exact custom-port URL.
• Confirm Printbuddy is using the current PrusaLink secret/password or API key.
• Check whether the file already exists on the printer's USB storage before retrying the same upload.
• If retrying returns 409 Conflict, the file may already exist, be locked, or be left as a placeholder from an interrupted upload.
• If upload succeeds but start-after-upload fails, check whether the file is visible in the printer's USB file list; upload and start are separate PrusaLink requests.
• If the backend logs mention Bambu FTP paths, .3mf rewriting, or Moonraker gcodes paths for a PrusaLink target, the wrong provider path is being used.

For same-name conflicts, use the conflict choices in the upload dialog when available:

• Upload as copy to keep the existing printer file.
• Delete existing and upload to replace the existing printer file.

PrusaLink USB file download is not currently implemented in Printbuddy, so the File Manager download action is hidden for Prusa printers.