code: def _initialize_trunk_interfaces_to_none(self, switch_ip, replay=True):
          
  
          try:
              # The following determines if the switch interfaces are
              # in place.  If so, make sure they have a basic trunk
              # configuration applied to none.
              switch_ifs = self._mdriver._get_switch_interfaces(
                  switch_ip, cfg_only=(False if replay else True))
              if not switch_ifs:
                  LOG.debug("Skipping switch %s which has no configured "
                            "interfaces",
                            switch_ip)
                  return
              self._driver.initialize_all_switch_interfaces(
                  switch_ifs, switch_ip)
          except Exception:
              with excutils.save_and_reraise_exception():
                  LOG.warning("Unable to initialize interfaces to "
                              "switch %(switch_ip)s",
                              {'switch_ip': switch_ip})
                  self._mdriver.register_switch_as_inactive(switch_ip,
                      'replay init_interface')
  
          if self._mdriver.is_replay_enabled():
              return
docs: Initialize all nexus interfaces to trunk allowed none.