'Failover all volumes to secondary.'

def failover_host(self, context, volumes, secondary_id=None, groups=None):

    if (secondary_id == 'default'):
        (secondary_id, volumes_update) = self._failback(volumes)
    elif ((secondary_id == self.replica_dev_conf['backend_id']) or (secondary_id is None)):
        (secondary_id, volumes_update) = self._failover(volumes)
    else:
        msg = (_('Invalid    secondary    id    %s.') % secondary_id)
        LOG.error(msg)
        raise exception.VolumeBackendAPIException(data=msg)
    return (secondary_id, volumes_update, [])
