The value range for the priority is between 1 and 90, the higher value also means the higher priority. A priority of 0 prevents this interface from being used for synchronization. In the case of special errors, interfaces which may be used temporarily for synchronization must be assigned an appropriate priority and the barring must be set to YES. Thus the synchronization direction can be turned without the necessity to switch the route on and off as is the case with the change of priority =0. Before changing barring from YES to NO, make sure that it has been changed from NO to YES on the other side. This priority assignment is to prevent the fatal error of a synchronization loop with regard to all route failures.