def set_backup_mgt(self, interface_id):
        """
        Set this interface as a backup management interface.
        
        Backup management interfaces cannot be placed on an interface with
        only a CVI (requires node interface/s). To 'unset' the specified
        interface address, set interface id to None
        ::
        
            engine.interface_options.set_backup_mgt(2)
            
        Set backup on interface 1, VLAN 201::
    
            engine.interface_options.set_backup_mgt('1.201')
        
        Remove management backup from engine::
        
            engine.interface_options.set_backup_mgt(None)
     
        :param str,int interface_id: interface identifier to make the backup
            management server.
        :raises InterfaceNotFound: specified interface is not found
        :raises UpdateElementFailed: failure to make modification
        :return: None
        """
        self.interface.set_unset(interface_id, 'backup_mgt')
        self._engine.update()
Set this interface as a backup management interface.
        
        Backup management interfaces cannot be placed on an interface with
        only a CVI (requires node interface/s). To 'unset' the specified
        interface address, set interface id to None
        ::
        
            engine.interface_options.set_backup_mgt(2)
            
        Set backup on interface 1, VLAN 201::
    
            engine.interface_options.set_backup_mgt('1.201')
        
        Remove management backup from engine::
        
            engine.interface_options.set_backup_mgt(None)
     
        :param str,int interface_id: interface identifier to make the backup
            management server.
        :raises InterfaceNotFound: specified interface is not found
        :raises UpdateElementFailed: failure to make modification
        :return: None