'Return the current state of the volume service.
If \'refresh\' is True, run the update first.'

def _update_volume_stats(self, refresh=False):

    data = {}
    pools = self._get_pools()
    data['volume_backend_name'] = self.configuration.safe_get('volume_backend_name')
    location_info = ('%(driver)s:%(host)s:%(volume)s' % {'driver': self.__class__.__name__, 'host': self.configuration.san_ip, 'volume': self.configuration.dpl_pool})
    try:
        (ret, output) = self.dpl.get_server_info()
        if (ret == 0):
            data['vendor_name'] = output['metadata']['vendor']
            data['driver_version'] = output['metadata']['version']
            data['storage_protocol'] = 'iSCSI'
            data['location_info'] = location_info
            data['consistencygroup_support'] = True
            data['consistent_group_snapshot_enabled'] = True
            data['pools'] = pools
            self._stats = data
    except Exception as e:
        LOG.error('Failed    to    get    server    info    due    to    %(state)s.', {'state': e})
    return self._stats
