# Core Infrastructure Services

This directory contains the core infrastructure services that form the foundation of the homelab. These services should be deployed **on the main server only** and are critical for the operation of all other services across all servers.

## Services

### DuckDNS
- **Purpose**: Dynamic DNS service for domain resolution and wildcard SSL certificates
- **Subdomain**: Configurable via environment variables
- **Token**: Configured in environment variables
- **SSL Certificates**: Generates wildcard cert used by all services on all servers
- **Deploy**: Core server only

### Traefik (v3)
- **Purpose**: Reverse proxy and SSL termination with multi-server routing
- **Ports**: 80 (HTTP), 443 (HTTPS), 8080 (Dashboard)
- **Configuration**: Located in `traefik/config/traefik.yml`
- **Multi-Server**: Discovers services on all servers via Docker providers
- **SSL**: Let's Encrypt with DNS-01 challenge (wildcard certificate)
- **Dashboard**: Available at configured domain
- **Deploy**: Core server (multi-provider), Remote servers (local-only)

**Note**: Sablier has been moved to its own stack (`/opt/stacks/sablier/`) and should be deployed on each server individually. See [Sablier documentation](../../docs/service-docs/sablier.md) for details.

### Authelia (v4.37.5)
- **Purpose**: Single sign-on authentication service for all services across all servers
- **Port**: 9091 (internal)
- **Access**: Configured authentication domain
- **Configuration**: Located in `authelia/config/`
- **Database**: SQLite database in `authelia/config/db.sqlite3`
- **Deploy**: Core server only

### DuckDNS
- **Purpose**: Dynamic DNS service for domain resolution and wildcard SSL certificates
- **Subdomain**: Configurable via environment variables
- **Token**: Configured in environment variables
- **SSL Certificates**: Generates wildcard cert used by all services on all servers
- **Deploy**: Core server only

## Multi-Server Architecture

The core stack on the main server provides centralized services for the entire homelab:

**Core Server Responsibilities:**
- Receives all external traffic (ports 80/443 forwarded from router)
- Runs DuckDNS for domain management and SSL certificates
- Runs Authelia for centralized authentication
- Runs multi-provider Traefik that discovers services on all servers
- Generates shared CA for Docker TLS communication

**Remote Server Setup:**
- Remote servers run their own Traefik instance (local Docker provider only)
- Remote servers run their own Sablier instance (local container management)
- Remote servers expose Docker API on port 2376 with TLS
- Core server Traefik connects to remote Docker APIs to discover services
- No port forwarding needed on remote servers

**Service Access:**
- All services accessible via: `https://service.yourdomain.duckdns.org`
- Core Traefik routes to appropriate server (local or remote)
- Single wildcard SSL certificate used for all services
- Authelia provides SSO for all protected services

## ⚠️ Version Pinning & Breaking Changes

### Authelia Version Pinning
**Current Version**: `authelia/authelia:4.37.5`

**Breaking Changes Identified**:
- Authelia v4.39.15+ has breaking configuration changes that are incompatible with the current setup
- Database schema changes may require migration or recreation
- Configuration file format changes may break existing setups

**Action Taken**:
- Pinned to v4.37.5 which is confirmed working
- Database recreated from scratch to ensure compatibility
- Configuration files verified and working

**Upgrade Path**:
- Test upgrades in a separate environment first
- Backup configuration and database before upgrading
- Check Authelia changelog for breaking changes
- Consider using Authelia's migration tools if available

### Traefik Version Pinning
**Current Version**: `traefik:v3`

**Notes**:
- Traefik v3 is stable and working with current configuration
- Configuration format is compatible
- No breaking changes identified in current setup

## Configuration Requirements

### File Structure
```
core/
├── docker-compose.yml          # Main service definitions
├── .env                        # Environment variables
├── authelia/
│   └── config/
│       ├── configuration.yml   # Authelia main config
│       ├── users_database.yml  # User credentials
│       └── db.sqlite3          # SQLite database
├── duckdns/
│   └── config/                 # DuckDNS configuration
├── traefik/
│   ├── config/
│   │   └── traefik.yml         # Traefik static config
│   ├── dynamic/                # Dynamic configurations
│   │   ├── routes.yml
│   │   ├── sablier.yml
│   │   └── external-host-*.yml # Remote server routing
│   └── letsencrypt/
│       └── acme.json           # SSL certificates
└── shared-ca/                  # TLS certificates for multi-server
    ├── ca.pem                  # Certificate Authority
    ├── ca-key.pem              # CA private key
    ├── cert.pem                # Client certificate
    └── key.pem                 # Client key
```

### Environment Variables (.env)
```bash
# Required for proper operation
DUCKDNS_TOKEN=your_duckdns_token_here
DUCKDNS_SUBDOMAINS=your_subdomain
DOMAIN=yourdomain.duckdns.org
TZ=America/New_York
PUID=1000
PGID=1000
```

### Network Requirements
- Docker network: `traefik-network`
- External ports: 80, 443 must be accessible
- DNS resolution: Domain must point to server IP

## Deployment

### Prerequisites
1. Docker and Docker Compose installed
2. Ports 80/443 forwarded to server
3. DuckDNS account with valid token
4. Domain configured in DuckDNS

### Startup Order
1. `duckdns` - For DNS updates and SSL certificate generation
2. `traefik` - Reverse proxy (waits for SSL certificates)
3. `authelia` - Authentication service

**Note**: Sablier is now deployed separately in `/opt/stacks/sablier/` after core stack is running.

### Commands
```bash
# Start all services
docker-compose up -d

# Check status
docker-compose ps

# View logs
docker-compose logs -f [service-name]

# Restart specific service
docker-compose restart [service-name]
```

## Troubleshooting

### Common Issues
1. **Connection Refused**: Check if Traefik config file is in correct location (`traefik/config/traefik.yml`)
2. **SSL Certificate Issues**: Verify DuckDNS token and domain configuration
3. **Authelia Login Issues**: Check database file exists and configuration is valid
4. **Service Not Starting**: Check Docker logs for error messages

### Backup Strategy
- Configuration files are backed up automatically (see backup directories)
- Database should be backed up regularly
- SSL certificates are stored in `letsencrypt/acme.json`
- Use `backup.sh` script for automated backups

## Security Notes
- Authelia provides authentication for protected services
- All external traffic goes through Traefik with SSL termination
- Internal services communicate via Docker networks
- Dashboard access is protected by Authelia middleware

## Maintenance
- Monitor SSL certificate expiration (Let's Encrypt auto-renews)
- Keep Authelia version pinned until tested upgrades are available
- Regularly backup configuration and database files
- Check logs for security issues or errors
- Run `./backup.sh` regularly to backup critical files

## Customization

### Domain Configuration
Update the following files with your domain:
- `docker-compose.yml`: Traefik labels and Authelia configuration
- `authelia/config/configuration.yml`: Domain settings
- `.env`: Domain environment variables

### SSL Certificate Provider
Modify `traefik/config/traefik.yml` to use different DNS providers:
```yaml
certificatesResolvers:
  letsencrypt:
    acme:
      dnsChallenge:
        provider: cloudflare  # or other supported provider
```

### Adding New Services
1. Add service definition to `docker-compose.yml`
2. Configure Traefik labels for routing
3. Add middleware for authentication if needed
4. Update network configuration