}
                        }
                        dc_list[i] = null;
                    }
                }

                /* No DCs found, for retieval of list by expiring it and retry.
                 */
                dc_list_expiration = 0;
            } while (retry-- > 0);

            dc_list_expiration = now + 1000 * 60 * 15; /* 15 min */
}