Cisco NCS 1002, Руководство по устранению неисправностей

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LOM Alarm
Default Severity: Critical (CR), Service-Affecting (SA)
Logical Objects: TRUNK
The Optical Transport Unit (OTU) Loss of Multiframe (LOM) alarm is an OTN alarm for the trunk port and
occurs when the Multi Frame Alignment Signal (MFAS) is corrupted. This alarm is raised when the MFAS
overhead field is invalid for more than five frames and persists for more than 3 milliseconds.
Clear the LOM Alarm
Step 1 Ensure that the fiber connector for the card is completely plugged in.
Step 2 If the bit error rate (BER) threshold is correct and at the expected level, use an optical test set to measure the power level
of the line to ensure it is within guidelines.
Step 3
If the optical power level is good, verify that optical receive levels are within the acceptable range.
Step 4 If receive levels are good, clean the fibers at both ends according to site practice.
Step 5 If the condition does not clear, verify that single-mode fiber is used.
Step 6
If the fiber is of the correct type, verify that a single-mode laser is used at the far-end node.
Step 7
Clean the fiber connectors at both ends for a signal degrade according to site practice.
Step 8 Verify that a single-mode laser is used at the far end.
Step 9 If the problem does not clear, the transmitter at the other end of the optical line could be failing and require replacement
If the alarm does not get cleared, you need to report a Service-Affecting (SA) problem. Log into the Technical Support
Website at
http://www.cisco.com/c/en/us/support/index.html for more information or log into http://www.cisco.com/c/
en/us/support/web/tsd-cisco-worldwide-contacts.html to obtain a directory of toll-free Technical Support numbers for
your country.
LOS-P Alarm
Default Severity: Critical (CR), Service-Affecting (SA)
Logical Objects: TRUNK
The Loss of Signal Payload (LOS-P) alarm for the trunk layer indicates that the PPM or CFP does not get any
incoming payload signal. The purpose of the LOS-P alarm is to alert the user that no optical power is being
received from the fiber. A common fault condition signaled by this alarm is a fiber cut. In this case, neither
the payload nor the overhead signals are received.
Clear the LOS-P Alarm
Step 1 Verify that the trunk port is configured with the proper wavelength. For more information see the Cisco NCS 1000 Series
Configuration Guide .
Step 2
Verify if there is a loss of received optical power. Compare the actual power levels with the expected power range..
Step 3
Verify the fiber continuity to the port of the NCS 1002 and fix the fiber connection.
Troubleshooting Guide for Cisco NCS 1002, IOS XR Release 6.3.x
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Alarm Troubleshooting
LOM Alarm