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alarm (optics-options)


Hierarchy Level


Specify the action to take if the receiving optics signal is below the optics low-light alarm threshold. Starting in Junos OS Release 15.1, for all QSFP-based interfaces, you need not explicitly configure the syslog option. The syslog option is enabled by default.


low-light-alarm—Enable the low light alarm.

link-down—Drop the 10-Gigabit Ethernet link and marks link as down.

syslog—Write the optics information to the system log.

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 10.0.