optix osn 8800 6800 3800 troubleshooting(v100r007)

OptiX OSN 8800/6800/3800V100R007C00

Troubleshooting

Issue 05Date 2013-11-30

HUAWEI TECHNOLOGIES CO., LTD.

Copyright Huawei Technologies Co., Ltd. 2013. All rights reserved.No part of this document may be reproduced or transmitted in any form or by any means without prior writtenconsent of Huawei Technologies Co., Ltd. Trademarks and Permissions

and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd.All other trademarks and trade names mentioned in this document are the property of their respective holders. NoticeThe purchased products, services and features are stipulated by the contract made between Huawei and thecustomer. All or part of the products, services and features described in this document may not be within thepurchase scope or the usage scope. Unless otherwise specified in the contract, all statements, information,and recommendations in this document are provided "AS IS" without warranties, guarantees or representationsof any kind, either express or implied.

The information in this document is subject to change without notice. Every effort has been made in thepreparation of this document to ensure accuracy of the contents, but all statements, information, andrecommendations in this document do not constitute a warranty of any kind, express or implied. Huawei Technologies Co., Ltd.Address: Huawei Industrial Base

Bantian, LonggangShenzhen 518129People's Republic of China

Website: http://www.huawei.comEmail: [email protected]

Issue 05 (2013-11-30) Huawei Proprietary and ConfidentialCopyright Huawei Technologies Co., Ltd.

i

About This Document

Related VersionsThe following table lists the product versions related to this document.

Product Name VersionOptiX OSN 8800 V100R007C00OptiX OSN 6800 V100R007C00OptiX OSN 3800 V100R007C00iManager U2000 V100R006C02iManager U2000 Web LCT V100R006C02

Intended AudienceThe intended audiences of this document are:l Field maintenance engineersl Network monitoring engineersl System maintenance engineers

Symbol ConventionsThe symbols that may be found in this document are defined as follows.

Symbol DescriptionIndicates an imminently hazardous situation which, if notavoided, will result in death or serious injury.

Indicates a potentially hazardous situation which, if notavoided, could result in death or serious injury.

OptiX OSN 8800/6800/3800Troubleshooting About This Document


ii

Symbol DescriptionIndicates a potentially hazardous situation which, if notavoided, may result in minor or moderate injury.

Indicates a potentially hazardous situation which, if notavoided, could result in equipment damage, data loss,performance deterioration, or unanticipated results.NOTICE is used to address practices not related to personalinjury.Calls attention to important information, best practices andtips.NOTE is used to address information not related to personalinjury, equipment damage, and environment deterioration.

GUI ConventionsThe GUI conventions that may be found in this document are defined as follows.

Convention DescriptionBoldface Buttons, menus, parameters, tabs, window, and dialog titles

are in boldface. For example, click OK.> Multi-level menus are in boldface and separated by the ">"

signs. For example, choose File > Create > Folder.

Change HistoryUpdates between document issues are cumulative. Therefore, the latest document issue containsall updates made in previous issues.

Updates in Issue 05 (2013-11-30) Based on Product VersionV100R007C00

This issue is the fifth official release for V100R007C00. Compared with Issue 04, some bugs inthe manual are fixed.



iii


This issue is the forth official release for V100R007C00. Compared with Issue 03, updating ofthe following content.

Update DescriptionBasic Conceptsand Methods ofFault Locating

Updated "Test Frame": optimized application 2 of ethernet test frame.

Fault LocationUsing TP-Assist

Updated the procedure of "Performing Intelligent Service FaultDiagnosis for Ethernet Services".


This issue is the third official release for V100R007C00. Compared with Issue 02 (2012-09-30),updating of SPC200 is added. This issue has the following updates.

Update DescriptionWhole manual l Deleted "Description" in the Chapter "General Fault Handling Flow"

l Deleted "Information Collecting and Recording" "TechnicalSupport" "Latest Technical Documentation Obtaining" in the Chapter"Fault Handling Flow"

l Deleted "Basic Rules for Locating Faults" in the Chapter "BasicConcepts and Methods of Fault Locating".

l Deleted "Configuration Data Analysis" in the Chapter "CommonMethods of Locating Faults"

l Deleted "Related Information" in the Chapter "Rectifying Bit Errors"l Deleted "Failure of Ringing of the Orderwire Phone Set upon

Incoming Calls Though the Calls Can Be Answered" in the Chapter"Rectifying Orderwire Problems"

l "Frequent Resetting of the SCC Board" has been moved from "17ECC Problems" to "10 NE Offline Problems".

l Added "Rectifying Coherent Board Faults".CommonMethods ofLocating Fault

Updated "Test Frame", added 100G OTU board.



iv


This issue is the second official release for V100R007C00. Only the issue number is updated.


First release for version V100R007C00. Compared with version V100R006C03, this issue hasthe following updates.

Update Description3.1 CommonFault IsolationMethods

Section "One-Click Data Collection" is added.

4 Fault LocationUsing TP-Assist

Section "Fault Location Using TP-Assist" is added.

15 PacketServiceProblems

Section "Rectifying Packet Service Problems" is added.

16 EthernetProblems

l Section "Common LAG Faults" is added.l Section "Common MSTP Faults" is added.

17 ECCProblems

l Section "FAQs for HWECC" is added.l Section "Troubleshooting for Inband DCN" is added.


The update of contents is described as follows:

Update Description3.1 Common Fault IsolationMethods

l 3.1.6 PRBS Test: Updated PRBS networkingapplications.

l 3.1.8 Test Frame: Added the 40G service type andthe supported board.

l Added "One-Click Data Collection".



v

Update Description12 Automatic SwitchingFailures

12.5 ODUk SNCP Protection: Updated the solution oftroubleshooting.

17 ECC Problems Added "FAQs for HWECC".


The update of contents is described as follows:

Update Description3.1 Common Fault IsolationMethods

Section "Port Mirroring Analysis" is added.Common fault diagnosis methods are optimized.

10.1 Unreachability of One NEby the U2000

Causes and diagnosis methods for the fault are modified.

12.12 DLAG Protection Changed "Automatic Switching Failure of DLAGProtection (OTN)" to "Automatic Switching Failure ofDLAG Protection".

13.10 DLAG Protection Changed "Automatic Reverting Failure of DLAGProtection (OTN)" to "Automatic Reverting Failure ofDLAG Protection".

Automatic Switching Failure ofDLAG Protection(OCS)Automatic Reverting Failure ofDLAG Protection(OCS)

Section are deleted.

14.4 IPA End Failure in aRaman System

Causes and diagnosis methods for the fault are added.


The update of contents is described as follows:Some bugs in the manual are fixed.



vi








Update Description12.16 Inter-SubrackCommunicationProtection

Section "Automatic Switching Failure of Inter-Subrack CommunicationProtection" is added.


This issue is the first official release for OptiX OSN 8800/6800/3800 V100R005C00. In thisrelease, the manuals for OptiX OSN 8800 V100R002C02, OptiX OSN 6800 V100R004C04,and OptiX OSN 3800 V100R004C04 are combined into one manual. Compared with thecombined manual, this issue has the following updates.



vii

Update DescriptionEntire manual This manual provides descriptions according to product series OptiX

OSN 8800, OptiX OSN 6800, and OptiX OSN 3800. Any differencebetween the products is described in the manual.

11 Board OfflineProblems

Section "Rectifying Board Offline Problems" is added.

16 EthernetProblems

Section "Service Interruption" is deleted.



viii

Contents

About This Document.....................................................................................................................ii1 Overview.........................................................................................................................................11.1 Safety Precautions..........................................................................................................................................................21.1.1 Laser............................................................................................................................................................................21.1.2 Short Circuit................................................................................................................................................................41.1.3 ESD..............................................................................................................................................................................41.1.4 Working on Equipment with Power Applied..............................................................................................................61.1.5 Alarm and Safety Symbols..........................................................................................................................................61.2 Instruments and Tools....................................................................................................................................................71.3 Maintenance Personnel Qualifications...........................................................................................................................82 Troubleshooting Workflow.........................................................................................................92.1 General Troubleshooting..............................................................................................................................................102.1.1 Workflow...................................................................................................................................................................102.2 Emergency Troubleshooting.........................................................................................................................................122.2.1 Workflow...................................................................................................................................................................122.2.2 Description.................................................................................................................................................................153 Fault Isolation Basics..................................................................................................................223.1 Common Fault Isolation Methods................................................................................................................................243.1.1 Service Signal Flow Analysis....................................................................................................................................243.1.2 Alarm and Performance Analysis..............................................................................................................................263.1.3 Fault Analysis Using Test Instruments......................................................................................................................293.1.4 Loopback...................................................................................................................................................................313.1.5 Replacement..............................................................................................................................................................323.1.6 PRBS Test..................................................................................................................................................................333.1.7 Configuration Modification.......................................................................................................................................353.1.8 Test Frame.................................................................................................................................................................363.1.9 RMON Performance Analysis...................................................................................................................................413.1.10 Port Mirroring Analysis...........................................................................................................................................433.1.11 One-Click Data Collection......................................................................................................................................464 Fault Location Using TP-Assist.................................................................................................494.1 Fault Location Using IP Ping.......................................................................................................................................50

OptiX OSN 8800/6800/3800Troubleshooting Contents


ix

4.2 E-LAN Service Loopback Detection............................................................................................................................524.3 Performing Intelligent Service Fault Diagnosis for Ethernet Services.........................................................................545 Service Interruptions..................................................................................................................565.1 Interruption of All Services..........................................................................................................................................585.2 Single-Channel Service Interruption on the Client Side..............................................................................................605.3 Single-Channel Service Interruption on the WDM Side..............................................................................................615.4 Service Interruption Caused by Human Misoperation.................................................................................................635.5 Service Interruptions Caused by Power Supply Failures.............................................................................................645.6 Service Interruptions Due to Grounding Fault.............................................................................................................665.7 Service Interruptions Due to Unfavorable Environmental Conditions.........................................................................675.8 Service Interruptions Due to Faulty Optical Fibers, Cables, or Connectors................................................................715.9 Service Interruptions Due to Inconsistency of Board Types or Board Settings...........................................................745.10 Service Interruptions on the VCTRUNK Port............................................................................................................755.11 Service Interruptions on a Single Ethernet Port.........................................................................................................775.12 Service Interruptions on All Ethernet Ports................................................................................................................795.13 Service Interruption Cases..........................................................................................................................................816 Transient Service Interruptions................................................................................................836.1 Transient Interruption of Main Path Services...............................................................................................................846.2 Transient Interruption of Single-Channel Services......................................................................................................856.3 Transient Service Interruptions on a Single VCTRUNK Port.....................................................................................876.4 Transient Service Interruptions on a Single Ethernet Port...........................................................................................936.5 Transient Service Interruptions Due to Protocol Related Causes.................................................................................976.6 Transient Interruption Cases.......................................................................................................................................1007 Optical Power Abnormity........................................................................................................1027.1 Abnormal Decline of the Optical Power....................................................................................................................1037.2 Optical Power Abnormity Cases................................................................................................................................1048 Bit Errors......................................................................................................................................1068.1 Multi-Channel Bit Errors............................................................................................................................................1078.2 Single-Channel Bit Errors..........................................................................................................................................1098.3 Bit Errors Due to Unfavorable Environmental Conditions........................................................................................1118.4 Bit Errors Due to Device Faults.................................................................................................................................1158.5 Bit Error Cases............................................................................................................................................................1179 A Fault in Pointer Justification...............................................................................................1189.1 Pointer Justification Due to Incorrect Clock Configuration.......................................................................................1199.2 Pointer Justification Due to Over-High Temperature and Humidity..........................................................................1209.3 Pointer Justification Due to Over-Low Precision of the External Clock Source.......................................................12110 NE Offline Problems..............................................................................................................12310.1 Unreachability of One NE by the U2000.................................................................................................................12410.2 Unreachability of All NEs in a Subnet by the U2000..............................................................................................125



x

10.3 Frequent Unreachability of an NE by the U2000.....................................................................................................12710.4 The System Control Board Is Frequently Reset.......................................................................................................12810.5 NE Offline Cases......................................................................................................................................................12911 Board Offline Problems......................................................................................................... 13011.1 A Board Is Offline....................................................................................................................................................13111.2 Multiple Boards Are Offline.....................................................................................................................................13112 Automatic Switching Failures...............................................................................................13312.1 Optical Line Protection.............................................................................................................................................13612.2 Intra-Board 1+1 Protection.......................................................................................................................................13812.3 Client-side 1+1 Protection........................................................................................................................................14112.4 SW SNCP Protection................................................................................................................................................14312.5 ODUk SNCP Protection...........................................................................................................................................14512.6 VLAN SNCP Protection...........................................................................................................................................14912.7 Tributary SNCP Protection.......................................................................................................................................15112.8 Automatic Switching Failure of DBPS Protection...................................................................................................15512.9 Board 1+1 Protection................................................................................................................................................15612.10 Ethernet Ring Protection........................................................................................................................................15712.11 MS SNCP Protection..............................................................................................................................................15912.12 DLAG Protection....................................................................................................................................................16212.13 Board-Level Protection...........................................................................................................................................16312.14 ODUk SPRing Protection.......................................................................................................................................16512.15 Optical Wavelength Shared Protection...................................................................................................................16812.16 Inter-Subrack Communication Protection..............................................................................................................17112.17 Linear Multiplex Section Protection.......................................................................................................................17112.18 MSP Ring...............................................................................................................................................................17412.19 Transoceanic MSP Ring.........................................................................................................................................17612.20 SNCP......................................................................................................................................................................17812.21 SNCTP....................................................................................................................................................................18012.22 Protection Cases.....................................................................................................................................................18213 Automatic Reverting Failures............................................................................................... 18413.1 Optical Line Protection.............................................................................................................................................18713.2 Intra-Board 1+1 Protection.......................................................................................................................................18913.3 Client-side 1+1 Protection........................................................................................................................................19113.4 SW SNCP Protection................................................................................................................................................19313.5 ODUk SNCP Protection...........................................................................................................................................19513.6 VLAN SNCP Protection...........................................................................................................................................19713.7 Tributary SNCP Protection.......................................................................................................................................20013.8 Ethernet Ring Protection..........................................................................................................................................20213.9 MS SNCP Protection................................................................................................................................................20313.10 DLAG Protection....................................................................................................................................................205



xi

13.11 ODUk SPRing Protection.......................................................................................................................................20713.12 Optical Wavelength Shared Protection...................................................................................................................20913.13 Linear Multiplex Section Protection.......................................................................................................................21113.14 MSP Ring...............................................................................................................................................................21213.15 Transoceanic Ring MS Protection..........................................................................................................................21313.16 SNCP......................................................................................................................................................................21413.17 SNCTP....................................................................................................................................................................21513.18 Protection Cases.....................................................................................................................................................21614 Optical Power Management Problems................................................................................21914.1 IPA Start Failure.......................................................................................................................................................22014.2 IPA End Failure........................................................................................................................................................22214.3 IPA Start Failure in a Raman System.......................................................................................................................22414.4 IPA End Failure in a Raman System........................................................................................................................22814.5 ALC Start Failure.....................................................................................................................................................23214.6 APE Exceptions........................................................................................................................................................23414.7 Handling Anomalies in the OPA Function...............................................................................................................23714.8 Optical Power Management Cases...........................................................................................................................23714.8.1 Automatic Power Equilibrium (APE)....................................................................................................................23814.8.2 Automatic Level Control (ALC)...........................................................................................................................23814.8.3 Intelligent Power Adjustment (IPA)......................................................................................................................23814.8.4 Intelligent Power Adjustment (IPA) of Raman System........................................................................................23815 Packet Service Problems........................................................................................................24015.1 Handling MPLS Tunnel Faults.................................................................................................................................24115.2 Handling PW Faults..................................................................................................................................................24215.3 Native Ethernet Service Troubleshooting.................................................................................................................24315.4 PWE3 Ethernet Service Troubleshooting.................................................................................................................24515.5 Tunnel APS Troubleshooting...................................................................................................................................24716 Ethernet Problems...................................................................................................................25016.1 Service Degradation.................................................................................................................................................25116.2 LCAS Startup Failure...............................................................................................................................................25216.3 LPT Switching Failure..............................................................................................................................................25516.4 LB Test Failure.........................................................................................................................................................25516.5 Test Frames Unavailability.......................................................................................................................................25916.6 Common LAG faults................................................................................................................................................25916.7 Common MSTP faults..............................................................................................................................................26216.8 Ethernet Service Cases.............................................................................................................................................26517 ECC Problems...........................................................................................................................26617.1 ECC Communication Interruption............................................................................................................................26717.2 Intermittent ECC Communication............................................................................................................................26817.3 HWECC FAQ...........................................................................................................................................................269



xii

17.4 Troubleshooting for Inband DCN.............................................................................................................................27017.5 ECC Cases................................................................................................................................................................27318 Clock Problems........................................................................................................................27518.1 Failure of NodeBs to Trace Clock Signals...............................................................................................................27618.2 Synchronization Failure of the Physical-Layer Clock..............................................................................................27719 Orderwire Problems................................................................................................................28019.1 Orderwire Failure.....................................................................................................................................................28119.2 A Called Phone Set Cannot Exit the Conference Call State.....................................................................................28219.3 Orderwire Cases.......................................................................................................................................................28320 Coherent Board Faults............................................................................................................28421 Interconnection Faults............................................................................................................28721.1 Failure in Intercommunication with the Data Equipment........................................................................................28821.2 Failure in Intercommunication with the SDH Equipment........................................................................................28921.3 WDM and other OTN Equipment Interconnection Failures....................................................................................29121.4 Equipment Interconnection Cases............................................................................................................................292A Remote Maintenance Guide...................................................................................................294A.1 Overview....................................................................................................................................................................295A.2 Enabling Remote Maintenance User.........................................................................................................................295A.3 Creating Remote Maintenance..................................................................................................................................296B Glossary......................................................................................................................................298



xiii

1 OverviewAbout This Chapter

This topic describes safety precautions, introduces essential instruments and tools, and outlinesmaintenance personnel training requirements necessary for troubleshooting.

1.1 Safety PrecautionsThis section describes the safety operation guidelines. It contains personal safety guidelines andequipment operating guidelines. These guidelines must be strictly followed to avoid any injuryto human body or damage to equipment during equipment operation.1.2 Instruments and ToolsThis topic introduces the essential instruments and tools necessary for troubleshooting.1.3 Maintenance Personnel QualificationsTo quickly and accurately locate and resolve a fault in the optical transport system, maintenancepersonnel must have sufficient background knowledge and service skills and be familiar withthe network and the equipment used. This topic outlines the skills and knowledge thatmaintenance personnel require for troubleshooting the OptiX OSN equipment.

OptiX OSN 8800/6800/3800Troubleshooting 1 Overview


1

1.1 Safety PrecautionsThis section describes the safety operation guidelines. It contains personal safety guidelines andequipment operating guidelines. These guidelines must be strictly followed to avoid any injuryto human body or damage to equipment during equipment operation.

1.1.1 LaserWhen you install and maintain equipment, follow the safety precautions described below to helpprevent personal injury or equipment damage. The laser complies with IEC60825.The safety precautions of lasers consist of two parts:l Personal injuryl Equipment damage

Personal Injury

DANGERLaser beams from the optical ports on boards or from the fiber connectors cause eye damage.Do not look directly at the optical ports or fiber connectors during the installation andmaintenance of boards or fibers. Do not shine laser beams into the eyes of other workers.

DANGERTo prevent eye damage in the case of an optical port that is in use, use protective caps to coverthe optical interface and the fiber connector after you remove the fiber from the optical interface.

DANGERThe optical power of the LINE interface on the Raman amplifier board is very high. Shut downthe pump laser before you insert or remove fiber connectors on the Raman amplifier board tohelp prevent personal injury that is caused by high optical power.



2

Equipment Damage

CAUTIONUse protective caps to cover unused optical ports and fiber connectors so that they do not gatherdust.

CAUTIONWhen performing a hardware loopback test on optical ports using a fiber, add an opticalattenuator to prevent damage to the equipment because of the high power of the laser beam. Addthe attenuator at the receive optical port on a board that supports optical attenuators.

CAUTIONWhen you use the optical time domain reflectometer (OTDR), disconnect the fiber between theopposite station and the board to prevent damage to the receive optical module because of highoptical power.

CAUTIONExercise caution when you remove or insert a board that is connected with fibers.



3

CAUTIONThe optical power of the Raman amplifier board is very high. Observe the following precautionswhen using the Raman amplifier board to prevent damage to the equipment.l Do not use fiber connectors within 020 km. The fibers at every joint point must be spliced.l The single-point additional loss within 010 km must be smaller than 0.1 dB (G.652) or

0.2 dB (G.655) and the single-point return loss must not be smaller than 40 dB.l The single-point additional loss within 1020 km must be smaller than 0.2 dB (G.652) or

0.4 dB (G.655) and the single-point return loss must not be smaller than 40 dB.l Fiber connections must be complete before you enable the lasers on the Raman amplifier

board. Make sure that the fiber connectors are clean. Otherwise, the fiber connectors mightbe damaged when you insert or remove the fiber connectors.

l The optical power of the LINE interface on the Raman amplifier board is very high. TheLSH/APC optical connectors must be used in the fiber that is connected to the LINEinterface.

l For the Raman amplifier board with backward pump, the strong pump light enters the fiberthrough the input end (LINE) instead of the output end (SYS). Do not add boards or non-fiber devices, such as attenuators or fiber jumpers, at the input end.

l The bent radius of the fiber that is connected to the LINE interface on the Raman amplifierboard must be larger than 30 mm to prevent the fiber from being burned.

1.1.2 Short CircuitExercise caution where you place metallic tools so that you do not cause a short circuit in anyequipment.

CAUTIONDo not place tools, such as screwdrivers, on the air baffle.

CAUTIONEnsure that screws do not fall off into the subrack or chassis.

1.1.3 ESDDuring installation and maintenance, follow ESD procedures to prevent equipment damage:l Always wear an ESD wrist strap during the operation.l Check that the equipment is securely grounded.



4

CAUTIONWear a well-grounded ESD wrist strap whenever you touch equipment or boards. Make surethat the wrist strap touches your skin. Insert the ESD strap connector into the ESD socket of theequipment.

For information about how to wear an ESD wrist strap, see Figure 1-1.

Figure 1-1 Wearing an ESD wrist strap

NOTE

Insert the connector of the ESD strap into the equipment port. For details, see the Quick Installation Guide.

When you are following ESD procedures, take the following precautions:l Check the validity and functionality of the wrist strap. Its resistance value must be between

0.75 mega ohm to 10 mega ohm. If the wrist strap validity period (usually two years) hasexpired, or if the resistance value fails to meet requirements, replace it with a wrist strapthat provides the required resistance value.

l Do not touch a board with your clothing. Clothing generates static electricity that is notprotected by the wrist strap.

l Wear an ESD wrist strap and place the board on an ESD pad when you replace boards orchips. Use ESD tweezers or extraction tools to replace chips. Do not touch chips, circuits,or pins with your bare hands.

l Keep the boards and other ESD-sensitive parts you are installing in ESD bags. Place theremoved boards and components on an ESD pad or ESD material. Do not use non-antistaticmaterials such as white foams, common plastic bags, or paper bags to pack boards, and donot let these materials touch the boards.

l Wear an ESD wrist strap when operating the ports of boards because they are also ESD-sensitive. Discharge the static electricity of cables and protective sleeves before you connectthem to the ports.



5

l Keep packing materials (such as, ESD boxes and bags) available in the equipment roomfor packing boards in the future.

ESD complies with IEC Publication 1000, EN 55022, EN 55024, IEC 61000 and GR-1089-CORE.

1.1.4 Working on Equipment with Power AppliedWhen you perform operations on the equipment when power is applied, ensure that you take thesafety precautions to prevent personal injury or equipment damage.

DANGERDo not install or disassemble equipment when power is applied.

1.1.5 Alarm and Safety SymbolsDuring equipment installation and maintenance, observe the precautions indicated by the alarmand safety symbols to help prevent personal injury or equipment damage.Table 1-1 describes the alarm and safety symbols on the WDM equipment.

Table 1-1 Symbols on the WDM equipmentSymbol Describes

ESD protection symbol.You must wear an ESD wrist strap or glove to avoiddamage caused by electrostatic discharge to boards.

HAZARD LEVEL 1M INVISIBLE LASER RADIATION

DO NOT VIEW DIRECTLY WITH NON-ATTENUATING OPTICAL

INSTRUMENTS

CAUTION

Laser level symbol.Indicates the laser level and warns that laser beamscan cause injuries to eyes.

Grounding symbol.Indicates the position of the grounding point.

Regular cleaning symbol.Warns you to regularly clean the air filter.



6

Symbol DescribesFan warning symbol.Warns you not to touch the fan blade until the fanstops moving.

1.2 Instruments and ToolsThis topic introduces the essential instruments and tools necessary for troubleshooting.Table 1-2 lists the instruments and tools used for troubleshooting.

Table 1-2 Instruments and tools used for troubleshootingName UsageOptical power meterFiber patch cord

Tests the optical power of optical ports.

Attenuator Attenuates the receive optical power.Optical spectrum analyzer Tests the system index.Optical time-domainreflectometer

Detects optical cable faults.

Adjustment pin Adjusts mechanical variable optical attenuators (VOAs).Fiberscope Checks whether the optical fiber end faces are clean.ESD wrist strip Protects sensitive components against static generated by the

human body.ESD bag Safely stores static-sensitive components.ESD uniform Protects sensitive components against static generated by the

human body.Phillips screwdriver Tightens and loosens screws on boards.Cassette cleaner Cleans optical fiber end faces.Dust-free cloth Cleans optical fiber heads.Special cleaning solvent(Isopropyl alcohol ispreferred to propyl alcohol)

Cleans optical fibers and flanges.

Special compressed gas Cleans boards and optical ports.U2000 Software used to configure and issue commands to boardsWeb LCT Software used to configure and issue commands to boards



7

Name UsageLabel Labels the replacement pigtails.Fiber binding strap Binds the replacement pigtails.

1.3 Maintenance Personnel QualificationsTo quickly and accurately locate and resolve a fault in the optical transport system, maintenancepersonnel must have sufficient background knowledge and service skills and be familiar withthe network and the equipment used. This topic outlines the skills and knowledge thatmaintenance personnel require for troubleshooting the OptiX OSN equipment.

Background Knowledgel WDM fundamentalsl The WDM system alarm generation mechanisml Troubleshooting methods for common alarms

Basic Operationsl Basic transmission equipment operationsl Basic network management system (NMS) operationsFor basic NMS operations, refer to the OptiX iManager U2000 Operator Guide or the on-linehelp.

Common Test InstrumentsCommonly needed transmission system test instruments include optical power meter, SDH/SONET tester, SmartBits tester, optical spectrum analyzer, OTDR and communication signalanalyzer. Refer to the respective operator guide for more information.

Network LayoutThe network layout of the projectThe service configuration, wavelength assignment, optical distribution frame (ODF), fiberrouting, board version, and equipment layout in each office.The current equipment running status in local officeThe relevant engineering files and documents (which need to be updated periodically)

On-Site Data CollectionThis process includes periodic data collection both when the equipment is running normally andwhen faults occur. Before handling the fault, maintenance personnel should first collect andstore the on-site data. For more information about data collection, refer to "3.1.11 One-ClickData Collection".



8

2 Troubleshooting WorkflowAbout This Chapter

This topic describes the troubleshooting process, information collection, and how to obtainadditional technical support and the latest technical documentation.

2.1 General TroubleshootingThis topic describes how to handle general faults.2.2 Emergency TroubleshootingThis topic describes how to handle emergencies.

OptiX OSN 8800/6800/3800Troubleshooting 2 Troubleshooting Workflow


9

2.1 General TroubleshootingThis topic describes how to handle general faults.

2.1.1 WorkflowThis topic describes how to handle general faults.The following figure describes how to handle general faults.



10

Figure 2-1 General troubleshooting flowchart

Start

Collect and recordinformation

External causes? Other handling process

Analyze and locate fault

Fault cleared?

Feed back to Huawei

Work out solutionstogether

Try to solve

Observe the runningequipment

Fault cleared?

Summary and fill outreport

End

Service recovery?

Yes

Yes

No

No

No

No

Yes

Yes



11

Fault Information CollectionThe following information needs to be recorded:l Fault occurrence timel Operations performed before and after the occurrence of the faultAdditionally, other important data, such as alarm information and performance events on theU2000, also needs to be saved.

External FaultsHandle faults caused by any of the following external factors:l Power failurel Optical cable faultl Environment variable (for example, telecommunications room temperature)l Terminal equipment

Technical SupportContact Huawei Customer Service Center (CSC) for assistance locating and resolving any issuesbeyond the scope of this document.You can also contact the technical support personnel in Huawei's local representative office ineither of the following ways:l Hotline: 4008302118l E-mail: [email protected]

Observation and ConfirmationAfter services are restored, observe services for 24 consecutive hours to confirm that the faulthas been resolved.

Troubleshooting ReportsAfter the fault is resolved, fill in the related troubleshooting report in a timely manner andsummarize how the fault was handled.

2.2 Emergency TroubleshootingThis topic describes how to handle emergencies.

2.2.1 WorkflowThis topic describes emergency handling workflow.The emergency handling flow refers to the fault handling flow when the service of the equipmentis interrupted due to external faults (such as power supply fault or fiber cut), misoperations, or



12

software/hardware faults of the equipment. In the case of the OptiX WDM optical transmissionequipment, in addition to clearing the fault according to the troubleshooting flow, take otheremergency measures (such as providing standby channels) or ask for help in time to reduce theservice interruption duration. The emergency troubleshooting process refers to thetroubleshooting process when services on the equipment are interrupted due to external faults,such as a power failure or damaged fiber cables, incorrect operations, or software/hardware faultsof the equipment. For the OptiX WDM optical transmission equipment, in addition to clearingthe fault according to the troubleshooting process, take other emergency measures, such asproviding standby channels, or ask for help in time to reduce the duration of service interruption.

CAUTIONWhen handling service interruptions or other emergencies, note the following points:l Restore services as soon as possible. If a backup channel is available, switch services to the

backup channel.l Analyze the fault symptoms first, find the causes, and handle the fault.l When you fail to resolve a fault, contact Huawei technical support to troubleshoot the fault

and minimize the duration of service interruption.l During the handling process, record and save the original fault data.



13

Figure 2-2 Emergency troubleshooting flowchart 1Start, a fault is reported

Yes

No

Yes

NoYes

Have spare resources?

YesThe

R_LOS/R_LOF/MUT_LOS/IN_PWR-

LOW/PWR_HIGH/NE-unreachable alarm

exists?

Locate the faulty section along the signal

flow and confirm whether the NE is

unreachable

The power supply/optical cable

is faulty?Yes Yes

No

Check the SCC/OA/MUX/DEMUX

board on siteAll channels are

abnormal?

No

Handle the

external fault

The fault is cleared, end

Cancel the abnormal operation, end

Query the bit error performance and check

whether all channels have excessive bit

errors

Yes

No

The BUS_ERR alarm exists?

Yes

No

The OTU_LOF/OTU_LOM/ODU_LOF/ODU_LOM/ODUk_PM_SSF/ODUk

_PM_BDI alarm exists?

Yes

Yes

No

Replace the faulty board

YesCheck the bit error

performance and locate the channel with

excessive bit errors

The system OSNR/nonlinearity/fiber

jumper between the OTU and MUX/DEMUX board

is faulty?

Handle the fiber jumper/optical cable

faultNo

Check the OTU/MUX/DEMUX board


Yes

The fault is a system fault, go to

The fault is a cross-connect fault, go to

The fault is an OTN/electrical layer

fault, go to

The fault is a single-channel fault, go to

The fault is a multi-channel fault, go to

Check alarms with the NMS1

Adjust the affected services to the backup resources, go

to 1

2

3

4

5

6

No

An abnormal operation is performed?



14

Figure 2-3 Emergency handling flow chart 2

a

The system OSNR or nonlinearity is improper or

the fiber jumper/optical cable is faulty?

No

Yes

Check the OA/MUX/DEMUX

board at the local/opposite end


Handle the fiber jumper/optical cable

fault


The cross-connection configuration is correct?

No

Yes

Modify the cross-connection

configuration

Replace the faulty tributary/line/cross-

connect board

The fiber connections between

OTU/tributary/line boards at the

local/opposite end are normal?

No

Yes

Handle the fiber connection fault

The TD/TF/LSR_WILL_DI alarm exists on the

OTU/line board at the local end?

Yes

Replace the faulty board at the local end

No

The LSR_WILL_DIE/OUT_PWR_HIGH/

OUT_PWR/LOW alarm exists on the OTU/line board at the opposite

end?

Replace the faulty board at the opposite

end

the transmit and receive optical power values are

abnormal?

Yes

boards at both the transmit and receive ends

Compare the current optical power of the OA/MUX/DEMUX board with the history normal value

No

The OA/MUX/DEMUX board is faulty?

Compare the current optical power of the OTU/tributary/line board of the faulty channel with the history normal value

The OTU/tributary/line board is faulty?

Replace the internal fiber between the OTU and MUX/DEMUX boards


Handle the fiber jumper/optical cable fault

No

No

YesYes

Handle the fiber jumper/optical cable fault

No


Yes


Cross-connection fault OTN/electrical layer fault

Single-channel faultMulti-channel fault

System fault2 3 4

5 6

a: The fiber connection faults include the inconsistency between the logical fiber

connection and the physical fiber connection , and the physical fiber connection faults.

a

Both

faulty?

The OA/MUX/DEMUX

are

2.2.2 DescriptionThis topic describes the emergency troubleshooting process.



15

Checking for Incorrect OperationsCheck for incorrect operations performed on the equipment, such as loopback or manual lasershutdown. If there are any, cancel them as required.

Restoring Services as Soon as PossibleWhen a fault occurs in the WDM system, services are interrupted. If a backup channel isavailable, switch the services to the backup channel to restore the services as soon as possiblebefore you begin troubleshooting the fault.

Handling Alarmsl If an R_LOS, R_LOF, MUT_LOS, IN_PWR_HIGH, IN_PWR_LOW, or NE-unreachable

alarm is reported, check and analyze the alarm. When such an alarm occurs, if the power supply or optical cable is faulty, handle these

faults first. Determine whether the fault is a multi-channel or single-channel issue based on the the

range of services affected, and handle it accordingly. If multiple channels are faulty, check the transmit/receive optical power and compare

the current optical power of the optical amplifier (OA)/multiplexer (MUX)/demultiplexer (DEMUX) board with the historical normal value. Check the networksection by section to determine whether the line, pigtail, or OA/MUX/DEMUX boardis faulty. Then handle the line/pigtail fault or replace the board accordingly.

If only one channel is faulty, compare the current optical power of the opticaltransponder unit (OTU)/tributary/line board on the faulty channel with the historicalnormal value to determine whether the board or intra-board fiber connection is faulty.Then replace the faulty board or change the internal fiber connections accordingly.

l If no R_LOS, R_LOF, MUT_LOS, IN_PWR_HIGH, IN_PWR_LOW, or NE-unreachablealarm is reported, check the bit error rate (BER) performance or optical power performancefor any of the following problems. If all channels have excessive bit errors, a system fault has occurred. Check the network

section by section along the signal flow to determine whether the system OSNR andnonlinearity are correct and whether the pigtail/optical cable is faulty. If the systemOSNR and nonlinearity are incorrect and the pigtail/optical cable is faulty, handle thepigtail/optical cable fault. If the pigtail/optical cable is functioning normally, the OA/MUX/DEMUX board is faulty and should be replaced.

If the fault is not a system fault and the BUS_ERR alarm is reported, the fault is a cross-connection fault. If the cross-connection configuration is incorrect, modify it to resolvethe fault. If it is correct, the tributary/line/cross-connect board is faulty and should bereplaced.

If the OTU_LOF/OTU_LOM/ODU_LOF/ODU_LOM/ODUk_PM_SSF/ODUk_PM_BDI alarm is reported, the OTN/electrical layer is faulty. Check whetherthe fiber connections between OTU boards, tributary boards, or line boards at the localand opposite ends are faulty. If any of these is faulty, handle the fiber connection faults,including the inconsistency between logical and physical fiber connections and physicalfiber connection faults.

If a TD/TF/LSR_WILL_DIE alarm is reported by an OTU/line board, the board is faultyand should be replaced.



16

TIPAs shown in the flowchart, optical-layer faults and fiber connection faults cause OTN alarms.Therefore, these faults must be handled first. After these faults are cleared, OTN alarms will typicallyclear also.

If you isolate the fault to a specific board, replace the board.Table 2-1 lists common alarms and their causes for the OA, MUX, DEMUX or OTU/tributary/line board.

Table 2-1 Common alarms and their causesBoard Type Alarm

aPossible Cause Action

OA board MUT_LOS Power-related alarmPossible cause:The received signals areabnormal.

Check whether the opticalpower of the upstreamoptical path and station isnormal.

PUM_BCM_ALMPUM_COOL_EXC

Temperature-related alarmPossible causes are asfollows:l The fan is powered off.l The ambient

temperature is too highor too low.

l The board is faulty.

l Power on the fan.l Adjust the ambient

temperature.l Replace the faulty

board.

OpticalMultiplexer/Demultiplexer Board

MUT_LOS Power-related alarmPossible cause:The received signals areabnormal.


MODULE_COOLCUR_OVER,MODULE_TEMP_OVER

Temperature-related alarm.Possible causes are asfollows:l The fan is powered off.l The ambient

temperature is too high.l The board is faulty.



board.

OTU/tributary/lineboard

R_LOS,IN_PWR_LOW,IN_PWR_HIGH

Power-related alarmPossible cause:The received signals areabnormal.




17

Board Type Alarma

Possible Cause Action

R_LOF,B1_EXC,B1_SD,B2_EXC,B2_SD

Power-related alarmPossible cause:The received signals areabnormal.If the module in the receiveend is faulty, these alarmswill also occur.

l Check whether theoptical power of theupstream optical pathand station is normal.

l Check whether theoptical power of thereceive end is normal.

TF, TD,OUT_PWR_LOW,OUT_PWR_HIGH

Mainly related to thetransmit unit of the board. Ifthe optical module on theboard is pluggable, checkthe module.

Check whether thepluggable optical moduleor the board is faulty.

LSR_COOL_ALM,LSR_WILL_DIE

Temperature-related alarmPossible causes are asfollows:l The fan is powered off.l The ambient

temperature is too high.l The pluggable optical

module is faulty.l The board is faulty.



module.l Replace the faulty

board.

NOTE

a: Common alarms are listed by board type in the table. Alarms for different boards of the same type maydiffer slightly.

In addition, there are various running and alarm indicators with different colors on the equipment.The On/Off and flashing states of these indicators indicate the current running state or possiblealarm of the equipment. Such indication helps you analyze the cause of the fault and accordinglyhandle the alarm. Refer to the Indicators.



18

CAUTIONIf you observe only the alarm indicators on the top of the cabinet, minor equipment alarms maybe missed (in the case of minor alarms, the alarm indicators on the top of the cabinet do not lightup, whereas the alarm indicators on the board do). In most cases, a minor alarm indicates apotential fault at the local or opposite end. Such alarms cannot be neglected.Equipment indicators indicate only the current operating status of the equipment, not the faultsthat have already occurred and been cleared.The indicator status that corresponds to a specific alarm category can be redefined on the U2000,and certain alarm types can even be suppressed.The board alarm indicator reports the alarm with the highest severity level detected by the board.

Isolating and Resolving External FaultsBefore locating a fault in the system, identify and resolve external faults, including optical cableor fiber faults, client equipment faults, and power failures.l Troubleshooting a client equipment fault

To troubleshoot a fault on client equipment, use either of the following methods: Method 1: Connect a bit error meter between the receive port and transmit port of the

OTU/tributary board and perform a bit error test. Use a pigtail to short-circuit thetransmit port of the corresponding OTU/tributary board at the opposite station to thereceive port of the corresponding OTU/tributary board. Check for bit errors for 24 hours.If no bit error is detected, the fault is occurring on the client side.

CAUTIONBefore short-circuiting the transmit port of the corresponding OTU/tributary board atthe opposite station to the receive port of the corresponding OTU/tributary board,determine whether to add an optical attenuator to the receive optical port on the OTU/tributary board. The appropriate optical attenuator is determined based on the opticalpower specification on the transmit port of the OTU/tributary board. Otherwise, opticalpower overload might damage the OTU/tributary board.

Method 2: For an OTU/tributary board that supports B1 bit error detection, comparewhether the RSES performance value of the OTU/tributary board at the local station isthe same as that at the opposite station. If they are the same, the system has no new biterrors and is operating normally, which indicates that the fault is located on the clientside.

Method 3: If users check client equipment on site, they can perform a self-loop (anoptical attenuator is required) on the receive and transmit optical ports of the clientequipment to check the alarms on the equipment. If alarms persist or the bit error meterstill detects bit errors, the fault is occurring on the client side.

l Troubleshooting an optical cable faultTo troubleshoot an optical cable fault, use any of the following methods:



19

Method 1: Test the input optical power of the local station and the output optical powerof the upstream station. If the difference between the two values (that is, the attenuation)is less than the designated value, the optical cable is functioning normally; otherwise,the optical cable is faulty.

Method 2: Check whether optical cable parameters such as the type and length meet thedesign requirements. If not, the optical cable is faulty.

Method 3: If the optical cable meets design requirements, check whether the opticalcable connector is properly attached. Ensure that the connection is normal.

Method 4: Switch system services to the backup optical cable. If the alarm is cleared,the optical cable is faulty.

Method 5: Use an OTDR to measure the optical power and determine whether the opticalcable is faulty. If the reflectance of the tested optical fiber core is less than 27 dB andthe attenuation of the fiber core is less than the designated value, the optical cable isfunctioning normally. Otherwise, the optical cable is faulty. Note that the OTDR has ablind spot within a short distance (smaller than 5 km), in which the test results areinaccurate.

CAUTIONWhen you use the OTDR, separate the optical fiber from the equipment. Otherwise, the intenseOTDR light might damage the equipment.

l Troubleshooting a power supply faultIf you cannot log in to a station and all boards connected to the station report alarms indicatinginput signal loss, the power supply of this station might be faulty. This causes a power failureat this station and triggers the alarm. If this station suddenly enters an abnormal operating status,the optical power of the station will suddenly decrease, some boards will operate abnormally,services will be interrupted, and abnormal login will occur. Check whether the power supplyvoltage of the transmission equipment is or a low-frequency transient voltage surge occurred.l Troubleshooting a grounding faultIf the equipment is struck by lightning or cannot be interconnected, check the grounding. Checkwhether the equipment is grounded in compliance with the specifications, whether anyequipment is disconnected from the public ground bar, and whether all types of equipment inthe same telecommunications room are grounded similarly. Then use an earth resistance testerto test whether the grounding resistance and the potential between working and protectiongrounds are within the permitted range.

Isolating and Resolving Optical Fiber or Board FaultsTo troubleshoot an optical fiber or board fault, use any of the following methods:l Method 1: Measure the input optical power of the board reporting the alarm and the output

optical power of the corresponding board at the opposite station. If the transmit optical power of the corresponding board at the opposite station is normal

and the difference between the receive optical power of the board at the local station



20

and the transmit optical power of the corresponding board at the opposite station isgreater than the designed value, the optical fiber is faulty.

If the transmit optical power of the corresponding board at the opposite station is toolow, the pluggable optical module on the board is faulty or the board is faulty.

l Method 2: Connect the board and optical meter using a new pigtail and measure the transmitoptical power of the board. If the measured optical power is normal, the original optical fiber is faulty. If the measured optical power is still too low, the pluggable optical module on the board

is faulty or the board is faulty.



21

3 Fault Isolation BasicsAbout This Chapter

This topic describes the basic concepts and methods used to locate faults.The key to locating faults is to pinpoint a fault to a single station.The general fault isolation rules are as follows:l Locate external faults first, followed by internal faults.l Locate network faults first, followed by NE faults.l Locate high-severity alarms first, followed by low-severity alarms.l Locate multi-channel signal alarms first, followed by single-channel signal alarms.l Locate bidirectional signal alarms first, followed by unidirectional signal alarms.l Locate public alarms first, followed by individual alarms.

Locate External Faults First, Followed by Internal FaultsBefore locating a fault, confirm that external conditions are normal. For example, no faults areoccurring in optical cables and fibers, client equipment, or power supply.

Locate Network Faults First, Followed by NE FaultsWhen a fault occurs on the transmission equipment, multiple stations, rather than a single station,may be reporting alarms. Fault analysis is required to quickly and accurately determine thestation at which the fault occurs.

Locate High-severity Alarms First, Followed by Low-severity AlarmsFirst analyze high-severity alarms, including critical and major alarms. Then analyze low-severity alarms, such as minor alarms and warnings.

OptiX OSN 8800/6800/3800Troubleshooting 3 Fault Isolation Basics


22

Locate Multi-channel Signal Alarms First, Followed by Single-channel SignalAlarms

When analyzing alarms, determine whether multiple channels are faulty or only a single channelis faulty. If multiple channels are faulty, locate the fault to the multiplex section (MS). After thefault of the MS is resolved, the single-channel alarm will be subsequently cleared.

Locate Bidirectional Signal Alarms first, Followed by Unidirectional Signal AlarmsWhen analyzing alarms, if alarms are present in both the local receive and opposite transmitdirections, check for similar faults in the opposite receive and local transmit directions. If alarmsare being reported in both directions, analyze and handle them first.

Locate Public Alarms First, Followed by Individual AlarmsWhen analyzing alarms, check whether they are public or individual alarms and determine thescope of their impact. That is, determine whether one or more boards are reporting the alarms.For a board with multiple optical ports, determine whether one, multiple, or all optical portshave bit errors.3.1 Common Fault Isolation MethodsThis topic provides common fault isolation methods.



23

3.1 Common Fault Isolation MethodsThis topic provides common fault isolation methods.Common methods for locating hardware faults can be briefly summarized as "First analyze, thenperform a loopback, and finally replace the board."When a fault occurs, first analyze the signal flow, alarms, and performance event data todetermine the possible faulty station or optical section. Then measure the optical power sectionby section, analyze the optical spectrum, and perform a loopback to isolate the fault to a specificboard. If the fault persists, replace the board or optical fiber.

3.1.1 Service Signal Flow AnalysisA common method for isolating faults is to check for faults along the signal flow, station bystation. This method allows you to quickly determine where the fault is occurring.The following example describes service signal flow analysis.

Application 1: Each Station Uses Tributary and Line Boardsl Fault description:

Figure 3-1 shows the networking structure of this example. A channel of client servicesfrom station A to station B is interrupted, and the client equipment at station B is either notreceiving optical signals or is receiving a large number of bit errors.

Figure 3-1 Signal flow analysis: Each station uses tributary and line boards

MUX OA OA DEMUX

MUXDEMUX OA OA

Station A

Client equipment

Station B

Client equipment

Line board

Tributary board

Tributary board

Line board

Signal Flow Fault Point

NOTEThe U2000 provides the service signal flow interface. For details on how to view the service signalflow using the GUIs, see "Viewing the Signal Flow Diagram for a WDM Trail" in the OnlineHelp.

l Fault analysis:

As shown in the preceding figure, the service signal flow of the client equipment at stationB is: client equipment at station A the tributary board at station A the cross-connectboard at station A the line board at station A MUX at station A OA at station A OA at station B DEMUX at station B the line board at station B the cross-connect board at station B the tributary board at station B client equipment at stationB.Possible causes are as follows:



24

The transmit unit of station A is faulty. The optical path (including the optical fibers and fiber connectors) is faulty. The receive unit of station B is faulty.1. Analyze the alarms and performance of the tributary board at station A. If the client-

side port of this tributary board receives no optical signal or its receive optical poweris too low, the fault location can be refined to the transmit end of the client equipmentat station A, the pigtail from the client equipment to the tributary board, or the client-side receive module of the tributary board.

2. If the client-side input optical power of the tributary board at station A is normal,check whether the cross-connection configuration is correct. If it is correct, locate thecorresponding line board based on the cross-connection. Then, check the alarms andperformance events of the tributary and line boards at station B for BUS_ERR alarms.If BUS_ERR alarms are reported, the fault may be occurring on the tributary, cross-connect, or line board. If needed, you can change the configuration or replace therelated boards.

3. If no BUS_ERR alarms are reported, check whether the output optical power of theline board is normal. If the optical power is abnormal, the fault is occurring on the lineboard.

4. The remaining steps are similar to the fault analysis steps of a tributary/line integratedboard.

Application 2: Each Station Uses the OTU boardl Fault description:

Figure 3-2 shows the networking structure. A channel of client services from station A tostation B are interrupted, and the client equipment at station B receives no optical signalsor receives a large number of bit errors.

Figure 3-2 Each Station Uses the OTU board in Application 2

OTU MUX OA OA DEMUX OTU

MUXDEMUX OA OA

Client equipment

Client equipment

Signal Flow Fault PointStation A Station B

NOTEThe U2000 provides the service signal flow interface. For information on how to view the servicesignal flow in GUIs, see "Viewing the Signal Flow Diagram for a WDM Trail" in the Online Help.

l Fault analysis:

The Client equipment at station B receives no optical signals or receives a large number ofbit errors. As shown in Figure 3-2, the service signal flow of the Client equipment at stationB is: Client equipment at station A OTU at station A MUX at station A OA at



25

station A OA at station B DEMUX at station B OTU at station B Clientequipment at station B. Possible causes are as follows: The transmit unit of station A is faulty. The optical path (including the fibers and fiber connectors) is faulty. The receive unit of station B is faulty.1. Analyze the alarms and performance of the OTU at station A. If the client-side

interface of this OTU receives no optical signal or its received optical power is toolow, locate the fault to the transmit end of the Client equipment at station A, the fiberjumper from the client equipment to the OTU, or the client side receiver module ofthe OTU.

2. If the input optical power of the OTU at station A is normal, check whether its outputoptical power is normal. If not, locate the fault to this OTU.

3. If the output optical power of the OTU at station A is also normal, observe whetherthe optical power of the MUX at station A sharply changes. If there are manywavelengths at station A, the loss of one of them does not results in a great change tothe optical power. Therefore, feed the signals at the MON port of the MUX to theMCA board and query for any loss-of-wavelength alarm.

4. The key components on the MUX are passive; therefore, the MUX is not likely to bedamaged. When the MCA detects the loss of a wavelength, the most possible faultpoint is between the fiber jumper from the OTU to the MUX.

5. The OA provides a function of input and output optical power detection. If the OA isfaulty, multiple wavelengths are affected. As a result, the possibility is rather low thatthe OA board is faulty.

6. At station B, analyze the signal flow in this order: OA at station B DEMUX atstation B OTU at station B Client equipment at station B. The method to analyzethe signal flow at station B is similar to that of station A.

3.1.2 Alarm and Performance AnalysisWhen a fault occurs in the system, it is usually accompanied by a large number of alarms andabnormal performance events. By analyzing this information, you can approximate the type andlocation of the fault.To review the alarms and performance events, do as follows:l Query the current or historical alarms and performance events on the U2000.l Review the running status or the severities of the alarms using the indicators on the open

rack and the boards.The U2000 fault isolation capabilities can be affected by system faults, and are classified asfollows:l Comprehensive: You are able to obtain fault information for the entire network.l Accurate: You are able to obtain the current alarms, alarm generation time, and historical

alarms of the equipment. In addition, you are able to obtain the specific values of theperformance events.

l Complex: In some cases, a significantly high number of alarms and performance eventscan make analysis very difficult.



26

l Dependent: Fault isolation is entirely dependent on the normal operations of the computer,software, and communication equipment. If any of these are faulty, fault isolationcapabilities may be limited or entirely lost.

CAUTIONl Before querying the performance data on the U2000, enable performance monitoring on the

U2000. Otherwise, the performance data will not be reported to the U2000.l Before querying the alarm or performance data on the U2000, ensure that the running time

of each NE is correctly set. Otherwise, the alarm and performance data will be incorrect ornot reported to the U2000.

l During maintenance, after re-issuing the configuration to a NE, set the NE time to the currenttime. Otherwise, the NE will operate at the incorrect default time.

The generation, detection, and transmission of an alarm varies with the OTU type and the typeof signals that the OTU receives. Alarm signal flow analysis allows you to quickly determinewhere the fault is occurring.

Application 1: Alarm Signal Flow for a Non-convergence OTU Board to ProcessSDH-compliant Signals

An R_LOS alarm generated by the OTU board at the local station is used as an example todescribe the alarm signal flow analysis when a non-convergent OTU board processes SONET/SDH standard signals, as shown in Figure 3-3.

Figure 3-3 Alarm and performance analysis: A Non-convergence OTU board processes SDH-compliant signals

OTU MUX OA OA DEMUX OTU

MUXDEMUX OA OA

Client equipment

Client equipment

Signal Flow Fault PointStation A Station B

NOTE

The automatic laser shutdown (ALS) function of the OTU board shown in the figure is disabled.



27

Figure 3-4 Alarm and performance analysis: fault isolation

R_LOSR_LOS REM_SF R_LOF

Station B Client deviceClient-side WDM-side WDM-side Client-side Client-device

Station A

xxx Detects and reports the xxx alarm.Alarm processing

As shown in Figure 3-4, the client side of the OTU board at station A receives R_LOS signals.The WDM side of this OTU board reports an R_LOS alarm and sends the fault information tostation B. The client side of the OTU board at station B reports the REM_SF alarm and sendsthe fault information to the downstream client device. The client device then reports anR_LOF alarm.If the client-side OTU board at station A reports the R_LOS alarm to the U2000, the client-sideequipment at station B reports the R_LOF alarm. In this case, the input signals on the client sideof the OTU board at station A are abnormal. Therefore, if the input signals on the client side ofthe OTU board at station A are abnormal, the client device is normal and the local device isfaulty.

Application 2: Alarm Signal Flow for a Non-convergence OTU Board to ProcessOTN-compliant Signals

In this example, a non-convergence OTU board is used to describe how to locate a fault usingalarm signal flow analysis after an OTU2_LOF alarm is generated when the board is processingOTN services. For other alarms, the fault analysis is similar. In Figure 3-5, ODU2 services aretransmitted on the line, and the optical fiber between station A and station B degrades.

Figure 3-5 Alarm and performance analysis: A non-convergence OTU board processes OTN-compliant signals

OTU

OTM

OTU

OTM

OTU-E

OTMOTM

Client equipment

Station A

OTU-WClient

equipment

Station B Station C

NOTE

The ALS function of the OTU board shown in this figure is disabled.


Issue 05 (2013-11-30) Huawei Proprietary and ConfidentialCopyright Huawei Te

optix osn 8800 6800 3800 troubleshooting(v100r007)

Documents

huawei trademarks

huawei proprietary

huawei industrial basebantian

hazardous situation

v100r007c00optix osn

versionoptix osn

important information

serious injury