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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:

Table 2: Optical Channel Interfaces

Entity Name

 

Fault Indicator

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

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.

Table 4: SONET/SDH Interfaces

Entity Name

 

Fault Indicator

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.

  1. Inspect the fiber connection, and ensure that the fiber is intact, thoroughly clean, and correctly connected to the port.
  2. Check for and clear all alarms raised against the far-end optical transmitter.
  3. 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.