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Hierarchy Level


The asynchronous-notification feature allows supported interfaces to generate and transfer link down alarms. This feature triggers the laser off (LOS) signal on an interface based on specific events and conditions and sends the LOS alarm to its peer (CE).

When you configure the asynchronous-notification knob on an interface, the LOS signal will be triggered under the following conditions:

  • RPD CCC Down Event: If the RPD (Routing and Policy Database) detects a CCC (Cross-Connect Circuit) down event, indicating a loss of connectivity for the associated service.

  • Interface Encapsulation: If the interface encapsulation is set to ethernet-ccc, ethernet-vpls, or vlan-ccc.

The LOS alarm will be sent to the peer CE (Customer Edge) device in these cases. This functionality is particularly useful for port-based services.


You can only configure the "asynchronous-notification" knob at the Interface Device (IFD) level. The RPD determines the CCC down event on a per Interface Logical (IFL) basis, while the Packet Forwarding Engine (PFE) sets the LOS alarm on the port. Also, This feature is not recommended for IFL-based services.

Also, the asynchronous-notification cannot be configured on aggregated Ethernet (ae) interfaces or their member links. Therefore, the LOS functionality triggered by the knob will not be available on ae interfaces.

By enabling the asynchronous-notification feature, you will receive timely notifications about link down events, allowing you to take appropriate actions or perform troubleshooting to ensure seamless network connectivity and service availability.


Support for notification of link down alarm generation and transfer is not enabled.

Required Privilege Level

interface—To view this statement in the configuration.

interface-control—To add this statement to the configuration.

Release Information

Statement introduced in Junos OS Release 8.3.