Copy below content to `src/Web/autopilot-monitor-web/staticwebapp.config.json` to enable maintenance mode for the web application. 
This will serve a maintenance page for all routes.

{
  "routes": [
    {
      "route": "/*",
      "serve": "/maintenance.html",
      "statusCode": 503
    }
  ]
}

and for disabling maintenance mode, simply remove the `staticwebapp.config.json` file or update it to 

{

}