Autonomous Server: Solar, LoRa, WLAN & SSD. Your digital fortress for communication & situational awareness in emergencies.
Le Réduit is a tribute to the Swiss National Redoubt strategy: A final, secure bastion when everything else fails.
This project documents the construction of a portable, energy-autonomous IT infrastructure inside a standardized Eurobox (Rako case). The system transforms a Raspberry Pi 4 into a Tactical Operations Center (TOC) for:
- Situational Awareness & Command: Real-time tracking and maps via TAK (Team Awareness Kit).
- Secure Communication: Encrypted chat and VoIP without the internet.
- Radio Bridge: Integration of LoRa (Meshtastic) into IP networks.
- Emergency Power Supply: Massive 100Ah battery capacity for days of operation without sun.
- 🔋 Energy Autonomy: 100W/200W foldable solar panel + Victron SmartSolar MPPT 100/20 + 100Ah LiFePO4 battery.
- 📡 Off-Grid Communication:
- LoRa: Meshtastic Node (868 MHz) for communication over kilometers without mobile networks.
- LTE: 4G/Cat-1 Bridge for hybrid connectivity when mobile networks are available.
- WLAN: High-Power Access Point (Atheros AR9271) for local team devices.
- 🛡️ Edge Cluster: Operates as a Single-Node Kubernetes Cluster (k3s) for maximum stability and "Infrastructure as Code".
- 💾 Hardware: Passively cooled aluminum housing ("Armor Case"), insulated Rako case, IP-certified feedthroughs.
A detailed shopping list can be found in BOM.md. Here are the main components:
- Battery: Hypery Smart 12V LiFePO4 (100Ah, Bluetooth, BMS)
- Solar: 100W/200W Foldable Panel & Victron SmartSolar MPPT 100/20
- Charging: SAE External Port & PACO 10A Mains Charger (Backup)
- Monitoring: Digital Voltmeter & Fuse Holder (16AWG)
- SBC: Raspberry Pi 4 Model B (8GB RAM)
- Storage: Intenso TOP SSD (256GB, SATA III) + USB 3.0 Adapter
- LoRa: Heltec WiFi LoRa 32 V3 (ESP32)
- WiFi: Atheros AR9271 USB Adapter (with external antenna)
- LTE: USB A7670G LTE Cat 1 Dongle (Global Bands)
- RTC: DS3231 Real Time Clock (for timestamps without internet)
- Box: Rako Container 600x400mm (60 Liters)
- Structure: Poplar plywood "Tech Deck" & Beechwood slat fixation
- Insulation: XPS Jackodur (20mm) for winter operation
The system follows a star-shaped 12V topology with central fusing.
See the Detailed Wiring Schema for the complete Mermaid diagram and pinout.
Key Connections:
- Solar Input: SAE Socket -> MPPT Controller
- Load: MPPT Load -> Main Switch -> Distributor -> DC-DC Converter -> Pi 4
- Data: SSD on USB 3.0 (Blue), Radio Modules on USB 2.0 (Interference Avoidance).
The system runs as a Single-Node Kubernetes Cluster based on k3s. This enables "Self-Healing" capabilities (if a service crashes, it is restarted) and professional deployment via Helm Charts.
- OS: Raspberry Pi OS Lite (64-bit)
- Cluster: k3s (Lightweight Kubernetes, optimized for Edge/IoT).
- Package Management: Helm. All services are defined as charts.
- Ingress: Traefik or Nginx Ingress for routing internal domains (e.g.,
tak.reduit.local). - Cert-Manager: Manages internal self-signed certificates for TLS encryption.
- OpenTAKServer:
- Deployed via Helm Chart.
- Central server for ATAK (Android Team Awareness Kit) clients.
- Provides position data, markers, chat, and "Data Packages" to all connected end devices.
- Hosts offline map tiles for the operational area.
- Matrix:
- High-Performance Matrix Server (written in Rust).
- Offers E2EE (End-to-End Encrypted) chats and file sharing.
- Extremely resource-efficient compared to Synapse.
- Mumble:
- VoIP server for tactical voice communication with low latency.
- Works reliably even with unstable connections.
- Meshtastic-Bridge:
- Custom Pod that mirrors messages from the LoRa USB stick into a Matrix room via Python API.
- Enables communication between WLAN users (ATAK/Matrix) and distant LoRa nodes.
This project uses large energy storage (LiFePO4 batteries).
- Short Circuit Hazard: A 100Ah battery can melt cables and cause fires in case of a short circuit. Fuses are mandatory!
- BMS & Monitoring: The LiFePO4 battery has an integrated BMS, but external fusing remains mandatory. Bluetooth monitoring allows checking cell status.
Pull Requests for Helm Charts, 3D printed parts (mounts), or configuration tips are welcome!
This project is published under the MIT License - see LICENSE file for details.
Built in Switzerland 🇨🇭 for when it matters.