Vite Hot Module Replacement (HMR) Connection Fails

1. Dev server not on correct host/port
2. WebSocket connection blocked by firewall/proxy
3. HMR host not configured for remote dev
4. HTTPS in production with HTTP dev server mismatch
5. Port not exposed in container/VM environment

Configure HMR in vite.config.js for remote dev:

export default {
  server: {
    hmr: {
      host: 'localhost',
      port: 5173,
      protocol: 'ws'
    }
  }
}

For remote development (Docker, VM):

hmr: {
  host: 'your-dev-server.com',
  port: 443,
  protocol: 'wss'
}