boot-to-talos-userdata.yaml

#cloud-config
write_files:
- path: /opt/boot-to-talos.sh
  permissions: '0755'
  content: |
    #!/bin/bash
    set -euo pipefail
    echo "🚀 Starting boot-to-Talos transition..."
    
    # Install Docker for image operations
    apt-get update
    apt-get install -y docker.io
    systemctl start docker
    
    # Configure Docker to use registry caches (critical - no direct internet from private subnets)
    mkdir -p /etc/docker
    cat > /etc/docker/daemon.json << 'DOCKER_EOF'
    {
      "registry-mirrors": ["http://10.10.1.100:5054"],
      "insecure-registries": ["10.10.1.100:5054"]
    }
    DOCKER_EOF
    systemctl restart docker
    
    # Pull custom Talos image via GHCR registry cache (port 5054)
    echo "📦 Pulling custom Talos image via bastion cache: 10.10.1.100:5054"
    echo "🔍 Image: ghcr.io/urmanac/cozystack-assets/talos:demo-stable"
    
    # Test if image is accessible
    docker pull "ghcr.io/urmanac/cozystack-assets/talos:demo-stable" || {
      echo "❌ Failed to pull ghcr.io/urmanac/cozystack-assets/talos:demo-stable"
      echo "🔍 Testing registry cache connectivity..."
      curl -v http://10.10.1.100:5054/v2/ || true
      exit 1
    }
    
    echo "✅ Successfully pulled ghcr.io/urmanac/cozystack-assets/talos:demo-stable"
    
    # Extract Talos kernel and initramfs for kexec
    echo "🔍 Extracting Talos kernel and initramfs..."
    docker create --name talos-extract "ghcr.io/urmanac/cozystack-assets/talos:demo-stable"
    
    # Find and extract boot files from the Talos image
    # This is a simplified approach - actual implementation may vary
    docker cp talos-extract:/boot /tmp/talos-boot/ 2>/dev/null || {
      echo "⚠️  /boot not found, looking for kernel files elsewhere..."
      docker run --rm "ghcr.io/urmanac/cozystack-assets/talos:demo-stable" find / -name "*vmlinuz*" -o -name "*initramfs*" || true
    }
    docker rm talos-extract
    
    # Transition to Talos (kexec)
    echo "🎯 Transitioning to Talos..."
    # Implementation depends on specific Talos image structure
    # This would invoke kexec with Talos kernel and initramfs
    echo "Boot-to-Talos preparation complete"
    
runcmd:
- /opt/boot-to-talos.sh
final_message: "Ubuntu → Talos transition initiated"