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LOF

Table 1: Alarm Details

Parameter	Description
Code	`lof`
Description	Loss of Frame: Either the frame-alignment process is in the out-of-frame (OOF) state or a severely-errored-frame defect is present on an incoming signal.
Entities Affected	Optical channel interfaces (see respective table below). OTN OTU interfaces (see respective table below). SONET/SDH interfaces (see respective table below).
Possible Causes	Either the fiber link or the optical connection is severely degraded. The far-end optical transmitter is faulty.
Default Severity	Critical
Service Affecting	Yes (true).
Alarm Clearing	See Clearing an LOF alarm.
Related Fault Hierarchy	See: Common fault hierarchy - OTN and CBR ports OTN interface fault hierarchy OC192, WAN PHY over OC192 interface fault hierarchy STM64, WAN PHY over STM64 interface fault hierarchy

Table 2: Optical Channel Interfaces

Entity Name		Fault Indicator
Entity Name	Module	Indicator	Status
och:<chassis>/<slot>/<2>/<1>/<subport.och>	UFM6	Fault LED, 200G line port	On

Table 3: OTN OTU Interfaces

Entity Name		Fault Indicator
Entity Name	Module	Indicator	Status
otu4:<chassis>/<slot>/<2>/<1>/<subport.och.tributary>	UFM6	Fault LED, 200G line port	On
otu4:<chassis>/<slot>/<1>/<1>	UFM4	Fault LED, 100G line port	On
otu4:<chassis>/<slot>/<subslot>/<port>	1x CFP BIC	Fault LED, 100G port
otu2:<chassis>/<slot>/<subslot>/<port>	12x SFP+ BIC	Fault LED, 10G port
otu2e:<chassis>/<slot>/<subslot>/<port> Note: Supported on UFM3 only.	12x SFP+ BIC	Fault LED, 10G port

Table 4: SONET/SDH Interfaces

Entity Name		Fault Indicator
Entity Name	Module	Indicator	Status
oc192:<chassis>/<slot>/<subslot>/<port>	12x SFP+ BIC	Fault LED, 10G port	On
wanoc192:<chassis>/<slot>/<subslot>/<port>
stm64:<chassis>/<slot>/<subslot>/<port>
wanstm64:<chassis>/<slot>/<subslot>/<port>

Clearing an LOF Alarm

Note

Follow all applicable safety requirements as described in the BTI7800 Series Hardware Overview and Installation Guide.

Inspect the fiber connection, and ensure that the fiber is intact, thoroughly clean, and correctly connected to the port.
Check for and clear all alarms raised against the far-end optical transmitter.
Check for alarms on the local interface.
- If the alarm has cleared, you have completed this procedure.
- If the alarm does not clear, contact your next level of support.