The dcn command enables the DCN feature on an interface.
The undo dcn command disables the DCN feature on an interface.
This command varies in transport and router modes. For detailed differences, see Differences Between Commands in Transport and Router Modes. This topic describes the command configuration in router mode.
Whether the DCN feature is enabled by default on an interface depends on the type of the board on which the interface resides and the number of interfaces on the board.
Usage Scenario
To implement the DCN functions, you must run the dcn command to enable the DCN feature on specified interfaces after you enable the DCN feature globally.
When you deploy an NE, check whether the DCN feature has been enabled on the interface that connects the NE to a live network. If the DCN feature has not been enabled, run the dcn command to enable it on the interface.Prerequisites
The DCN feature has been enabled globally using the dcn command in the system view.
Precautions
In VS mode, this command is supported only by the admin VS.
The dcn command can be run on the serial interfaces that are E1 channels in the timeslot range 1 to 31. If the timeslot range is not 1 to 31 or the DCN VLAN ID is the same as the service VLAN ID, the DCN function cannot be enabled on the interface. In this case, the device displays a message, prompting you to locate the cause of the DCN function failure. To check whether the DCN feature has taken effect on an interface, run the display dcn default-port command. After the undo dcn command is run, DCN is disabled and devices will be out of the NMS's control. Exercise caution when running this command.