When running multiple virtual printers with different access codes on
separate bind IPs, FTP connections were always routed to the wrong VP.
Root cause: the iptables REDIRECT rule (990→9990) rewrites the
destination IP to the incoming interface's primary address. With Linux's
weak host model (arp_filter=0), packets for secondary IPs arrive on the
primary interface, and REDIRECT sends them all to the first VP's FTP
server. MQTT was unaffected because port 8883 had no redirect.
Fix: FTP server now binds directly to port 990 (standard implicit FTPS),
eliminating the iptables redirect entirely. Requires CAP_NET_BIND_SERVICE
(already set in the systemd service file and Docker image).
Also removed a global asyncio set_exception_handler() in the MQTT server
that was overwritten by each VP instance, causing spurious "Unhandled
exception in client_connected_cb" errors on startup.
Changes:
- FTP_PORT: 9990 → 990 (ftp_server.py)
- Removed set_exception_handler() from MQTT server
- Updated Dockerfile, docker-compose.yml port mappings
- Deprecated --redirect-990 in install script
- Updated wiki: removed iptables instructions for all platforms
- Added migration guide (docs/migration-vp-ftp-port.md)
- Added unit tests for port constant and no-global-state invariant
Introduces a new "Proxy Mode" for the Virtual Printer that enables
remote printing from anywhere in the world without VPN, port forwarding,
or Bambu Cloud dependency.
Bambuddy acts as a TLS relay between a remote slicer (Bambu Studio/
OrcaSlicer) and the local Bambu Lab printer:
Remote Slicer → Internet → Bambuddy Server → Local Network → Printer
The slicer connects to Bambuddy using the real printer's serial number
and access code. Bambuddy authenticates and relays all FTP (file transfer)
and MQTT (commands/status) traffic with end-to-end TLS encryption.
- No port forwarding required - printer stays safely on local network
- No VPN needed - connect from coffee shops, hotels, work, anywhere
- No Bambu Cloud dependency - fully self-hosted solution
- End-to-end TLS encryption on FTP (port 9990) and MQTT (port 8883)
- Works with Bambu Studio and OrcaSlicer
- Uses real printer credentials for authentication
- Automatic printer selection from connected printers
- Add SlicerProxyManager class for TLS relay (tcp_proxy.py)
- TLS termination with auto-generated certificates
- Concurrent FTP and MQTT proxy servers
- Connection lifecycle management with proper cleanup
- Extend VirtualPrinterManager with proxy mode support
- New 'proxy' mode alongside archive/review/queue modes
- Target printer selection and credential management
- Add proxy configuration endpoints to settings API
- Add permission checks for proxy endpoints
- Add Proxy Mode card to Virtual Printer settings
- Target printer dropdown for proxy destination
- Real-time proxy status display (ports, target, running state)
- Full i18n support (English, German)
- Add network architecture diagram
- Add proxy mode section to README
- Add comprehensive guide to wiki
- Add prominent feature section to website
- Backend unit tests for SlicerProxyManager
- Backend unit tests for proxy mode configuration
- Frontend tests for proxy mode UI components
Closes#207#170
