code: def CreateServer(frontend=None):
    
    max_port = config.CONFIG.Get("Frontend.port_max",
                                 config.CONFIG["Frontend.bind_port"])
  
    for port in range(config.CONFIG["Frontend.bind_port"], max_port + 1):
  
      server_address = (config.CONFIG["Frontend.bind_address"], port)
      try:
        httpd = GRRHTTPServer(
            server_address, GRRHTTPServerHandler, frontend=frontend)
        break
      except socket.error as e:
        if e.errno == socket.errno.EADDRINUSE and port < max_port:
          logging.info("Port %s in use, trying %s", port, port + 1)
        else:
          raise
  
    sa = httpd.socket.getsockname()
    logging.info("Serving HTTP on %s port %d ...", sa[0], sa[1])
    return httpd
docs: Start frontend http server.