Configuring an Interface to Transit to Error-Down State When the Optical Power Is Low

Context

Low optical power on an Ethernet optical interface may cause problems such as packet loss. Because the interface is still in Up state, traffic is still transmitted on the interface even if a backup link is configured. To avoid impact on services, you can configure the interface to change to the Error-down state when the optical power is low. When the optical power on the interface falls below the lower alarm threshold, the system disables the interface and records the interface status as ERROR DOWN(transceiver-power-low) state (indicating that the interface is Down because of low optical power). Services are then switched to the backup link immediately.

Procedure

Run system-view

The system view is displayed.
Run interface interface-type interface-number

The interface view is displayed.
Run transceiver power low trigger error-down

The interface is configured to transit to the Error-down state when the optical power is low.

By default, an interface does not transit to the Error-down state when the optical power is low.

Verifying the Configuration

Run the display error-down recovery [ interface interface-type interface-number ] command in any view to check information about the interface in Error-down state.

Follow-up Procedure

An interface in Error-down state can be recovered using either of the following methods:

Manual recovery: If a few interfaces need to be recovered forcibly, run the shutdown and undo shutdown commands in the interface view. Alternatively, run the restart command in the interface view to restart the interfaces.
Automatic recovery: If a large number of interfaces need to be recovered, manual recovery is time consuming and some interfaces may be omitted. You can run the error-down auto-recovery cause transceiver-power-low interval interval-value command in the system view to enable automatic interface recovery and set the recovery delay time. An interface in Error-down state automatically recovers when the specified delay time expires.