code: def set_auth_request(self, interface_id, address=None):
          
          for engine_type in ['master', 'layer2', 'ips']:
              if engine_type in self.engine.type:
                  return
          
          interface = self.get(interface_id)
          if 'cluster' in self.engine.type:
              # Auth request on a cluster interface must have at least a CVI.
              # It cannot bind to NDI only interfaces
              if not any(isinstance(itf, ClusterVirtualInterface)
                         for itf in interface.all_interfaces):
                  raise InterfaceNotFound('The interface specified: %s does not have '
                      'a CVI interface defined and therefore cannot be used as an '
                      'interface for auth_requests. If setting the primary_mgt interface '
                      'provide an interface id for auth_request.' % interface_id)
          
          current_interface = self.get(
              self.engine.interface_options.auth_request)
          for itf in current_interface.all_interfaces:
              if getattr(itf, 'auth_request', False):
                  itf['auth_request'] = False
          # Set
          sub_if = interface.all_interfaces
          if any(isinstance(itf, ClusterVirtualInterface) for itf in sub_if):
              for itf in sub_if:
                  if isinstance(itf, ClusterVirtualInterface):
                      if address:
                          if getattr(itf, 'address', None) == address:
                              itf['auth_request'] = True
                      else:
                          itf['auth_request'] = True
          else:
              for itf in sub_if:
                  if getattr(itf, 'auth_request', None) is not None:
                      if address:
                          if getattr(itf, 'address', None) == address:
                              itf['auth_request'] = True
                      else:
                          itf['auth_request'] = True
docs: Set auth request, there can only be one per engine so unset all
          other interfaces. If this is a cluster, auth request can only be
          set on an interface with a CVI (not valid on NDI only cluster
          interfaces).
          If this is a cluster interface, address should be CVI IP.