docs: def _bind_fabric(self, context, segment):
          """Allocate dynamic segments for the port
  
          Segment physnets are based on the switch to which the host is
          connected.
          """
          port_id = context.current['id']
          physnet = self._get_physnet(context)
          if not physnet:
              LOG.debug("bind_port for port %(port)s: no physical_network "
                        "found", {'port': port_id})
              return False
  
          next_segment = context.allocate_dynamic_segment(
              {'network_id': context.network.current['id'],
               'network_type': n_const.TYPE_VLAN,
               'physical_network': physnet})
          LOG.debug("bind_port for port %(port)s: "
                    "current_segment=%(current_seg)s, "
                    "next_segment=%(next_seg)s",
                    {'port': port_id, 'current_seg': segment,
                     'next_seg': next_segment})
          context.continue_binding(segment['id'], [next_segment])
          return True