RAN17.1 Troubleshooting Guide(01)(PDF)-En

8/18/2019 RAN17.1 Troubleshooting Guide(01)(PDF)-En

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RAN17.1

Troubleshooting Guide

Issue 01

Date 2015-03-25

HUAWEI TECHNOLOGIES CO., LTD.


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Issue 01 (2015-03-25) Huawei Proprietary and ConfidentialCopyright © Huawei Technologies Co., Ltd

i

Copyright © Huawei Technologies Co., Ltd. 2015. All rights reserved.No part of this document may be reproduced or transmitted in any form or by any means without priorwritten consent 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 respectiveholders.

NoticeThe purchased products, services and features are stipulated by the contract made between Huawei andthe customer. All or part of the products, services and features described in this document may not bewithin the purchase 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 orrepresentations of 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, Longgang

Shenzhen 518129

People's Republic of China

Website: http://www.huawei.com

Email: [email protected]

http://www.huawei.com/mailto:[email protected]:[email protected]://www.huawei.com/


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RAN17.1 Troubleshooting Guide Contents


ii

Overview

Document PurposeThis document provides information on how to identify and repair common faults on RANequipment that is working in a live network. Operation and maintenance (O&M) personnelshould use this guide in the following scenarios:

User complaints are received Faults are detected in the routine maintenance processes Emergency faults are detected in the equipment Alarm analysis

Product VersionThe following table lists the product versions related to this document.

ProductName

ProductModel

Product Version Solution Version

RNC BSC6900 V900R017C10 RAN17.1

RNC BSC6910 V100R017C10

NodeB DBS3900 V100R010C10

Intended AudienceThis guide is intended for system engineers.

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

Symbol Description

Alerts you to a high risk hazard that could, if not avoided,result in serious injury or death.


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Symbol Description

Alerts you to a medium or low risk hazard that could, if notavoided, result in moderate or minor injury.

Alerts you to a potentially hazardous situation that could, if notavoided, result in equipment damage, data loss, performancedeterioration, or unanticipated results.

Provides a tip that may help you solve a problem or save time.

Provides additional information to emphasize or supplementimportant points in the main text.

Change HistoryChanges between document issues are cumulative. The latest document issue contains all thechanges made in earlier issues.

01 (2015-03-25)This issue includes the following changes:

Compared with issue RAN17.0 01 (2014-09-25), this issue includes the following changes:

Content Description

TechnicalChanges

Added N/A

Modified Updated the description of FMA

Fault Diagnosis

Hierarchical Delimitation

Recovery Confirmation

Information Collection

Deleted N/A

EditorialChanges

N/A


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Contents

Overview ........................................................................................................................................... ii

Contents ........................................................................................................................................... iv

1 Troubleshooting Process and Methods .................................................................................... 1

1.1 About this Chapter ......................................................... ................................................................. .................. 1 1.2 Troubleshooting Process .................................................................................................................................. 1

1.2.1 Flowchart ................................................................................................................................................ 1

1.2.2 Collecting and Recording Fault Information .................................................. ........................................ 2

1.2.3 Determining Fault Scope and Type ................................................................. ........................................ 3

1.2.4 Locating the Cause of the Fault ..................................... ............................................................... .......... 4

1.2.5 Troubleshooting ......................................................................................................... ............................. 5

1.2.6 Ensuring that System Is Repaired ................................................................... ........................................ 5

1.2.7 Recording the Troubleshooting Process .......................................................... ........................................ 5

1.2.8 Contacting Huawei for Technical Support ................................................................ .............................. 6

2 FMA ................................................................................................................................................. 1 2.1 Fault Overview .............................................................. ................................................................. .................. 2

2.2 Fault Diagnosis................................................................................................................................................. 4

2.3 Hierarchical Delimitation ......................................................... .............................................................. ........ 11

2.4 Recovery Confirmation .................................................................................................... .............................. 13

2.5 Information Collection ........................................................................................................ ........................... 13

3 Common Maintenance Functions ............................................................................................ 16 3.1 About This Chapter ....................................................................................... ................................................. 16

3.2 MBTS Emergency OM Channel ................................................................... ................................................. 16 3.2.1 Overview .............................................................. ................................................................. ................ 16

3.2.2 Application Scenarios ..................................................................................... ...................................... 17

3.2.3 Emergency OM Channel Establishment .............................................. ................................................. 19

3.2.4 Function Description ................................................................. ............................................................ 24

3.2.5 Troubleshooting ......................................................................................................... ........................... 28

3.2.6 Example of Using the Proxy MML Function ............................................................. ........................... 28

3.2.7 Other Operations ........................................................................................................ ........................... 34

3.3 Transmission Maintenance Function ............................................................. ................................................. 34

3.3.1 Checking for Faults in Crossed Pair Connections ................................................................ ................. 34


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3.3.2 Performing a Bit Error Monitoring on the E1/T1 Port .......................................................................... 35

3.3.3 Using VCLCC to Check for Link Faults ......................................................... ...................................... 36

3.3.4 Using VCLCC to Check for Link Delays ............................................................................................. 37

3.3.5 Using VCLPM to Check for Abnormal Links ............................................................ ........................... 38

3.3.6 Performing VCL Link Performance Query ................................................................ ........................... 39

3.3.7 Performing the IP over ATM OMCH Continuity Check ....................................................................... 40

3.3.8 Using LOP VCL to Check for Link Faults or Link Delays ................................................................... 41

3.3.9 Checking the Operating Status of the Ethernet Port .............................................................. ................ 42

3.3.10 Using the Ping Operation to Perform the IP Continuity Check ........................................................... 42

3.3.11 Using the Trace Operation to Check for Abnormal Transmission Nodes ............................................ 44

3.3.12 Using the Ping Operation to Check the IP Path Status ........................................................ ................ 45

3.3.13 Performing IP Loopback Detection to Check for Abnormal Transmission Nodes .............................. 46

3.3.14 Performing IP PM Detection to Check IP Path Performance on the Iub Interface .............................. 48

3.3.15 Performing IP PM Detection to Check IP Pool Performance on the Iub Interface .......... ................... 49 3.3.16 Performing Node Synchronization Detection to Check for Transmission Delay and Jitter on the UserPlane .............................................................................................................................................................. 49

3.3.17 Performing TWAMP Detection to Check for IP Link Performance .................................................... 51

3.4 Clock Maintenance Function.......................................................................................................................... 52

3.4.1 Querying the Status of the BSC Reference Clock ................................................................ ................. 52

3.4.2 Querying the Status of the BSC Board Clock ............................................................................... ........ 53

4 Troubleshooting HSPA Service Setup Failures .................................................................... 55 4.1 About This Chapter ....................................................................................... ................................................. 55

4.2 Definition of HSPA Service Setup Failures .............................................................. ...................................... 55 4.3 Related Information........................................................................................................................................ 55

4.4 Possible Causes .............................................................................................................................................. 56

4.5 Troubleshooting Flowchart ................................................................................................ ............................ 56

4.5.2 Troubleshooting Abnormal AAL2PATH,IPPATH or IPPOOL .............................................................. 56

4.5.3 Troubleshooting Failures to Admit HSUPA User Number and HSDPA User Number ......................... 58

4.5.4 Determining Whether the Service Rate Mismatch the Threshold of HSPA Services ............................ 60

4.5.5 Determining Whether the Terminal Supports the HSPA Services ......................................................... 61

4.6 Typical Cases ...................................................... ................................................................. ........................... 62

5 Troubleshooting HSUPA Data Transmission Faults ........................................................... 64 5.1 About This Chapter ....................................................................................... ................................................. 64

5.2 Definition of HSUPA Data Transmission Faults ......................................................................... ................... 64

5.3 Related Information........................................................................................................................................ 64

5.3.1 Requisites for Reaching HSUPA Maximum Rate ................................................................................. 64

5.4 Troubleshooting Low or Fluctuating HSUPA Rate ................................................................................ ........ 66

5.4.1 Fault Description ............................................................. ................................................................. ..... 66

5.4.2 Possible Causes ............................................................... ................................................................. ..... 66

5.4.3 Fault Handling Procedure ..................................................................................................................... 66

5.4.4 Typical Cases ....................................................... ................................................................. ................ 70


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6 Troubleshooting HSDPA Service Rate Faults ....................................................................... 72 6.1 About This Chapter ....................................................................................... ................................................. 72

6.2 Definition of HSDPA Service Rate Faults ................................................................ ...................................... 72


6.4 Troubleshooting Low or Fluctuating HSDPA Service Rate ................................................ ........................... 74


6.4.2 Fault Handling Flowchart ..................................................................................................................... 74

6.4.3 Checking Basic Elements ........................................................... ........................................................... 75

6.4.4 Determining Whether the Service Can Be Set Up ..................................................... ........................... 77

6.4.5 Determining Whether Radio Resources Are Limited ............................................................ ................ 81

6.4.6 Check Faults Segment by Segment ................................................................. ...................................... 82

6.4.7 Typical Cases ....................................................... ................................................................. ................ 85

7 Troubleshooting SLC Faults ..................................................................................................... 87

7.1 About This Chapter ....................................................................................... ................................................. 87

7.2 Definition of SLC Faults .......................................................... .............................................................. ........ 87

7.3 SLC Problem Monitoring ......................................................... .............................................................. ........ 87

7.4 Troubleshooting the Problem of No RRC Connection Request ..................................................................... 89


7.4.2 Possible Causes ............................................................... ................................................................. ..... 89


7.4.4 Typical Case 1 ............................................................................................................ ........................... 91

7.4.5 Typical Case 2 ............................................................................................................ ........................... 91

7.5 Troubleshooting RRC Connection Setup Failures......................................... ................................................. 92



8 Troubleshooting RRC Connection Setup Failures ............................................................... 93 8.1 Definition of RRC Access Failures ............................................................... ................................................. 93

8.2 Formula for the RRC Setup Success Rate ................................................................ ...................................... 93


8.4 Troubleshooting the Problem of No Replies to an RRC Connection Setup Request ..................................... 94

8.4.1 Failure Description .......................................................... .............................................................. ........ 94


8.4.3 Typical Case 1 ............................................................................................................ ........................... 97

8.4.4 Typical Case 2 ............................................................................................................ ........................... 99

8.5 Troubleshooting Rejected RRC Connection Setup Requests ......................................................... .............. 100

8.5.1 Failure Description .......................................................... .............................................................. ...... 100

8.5.2 Handling Procedure............................................................................................................................. 100

8.6 Troubleshooting Failures in Replying to RRC Connection Setup Requests ................................ ................ 102

8.6.1 Fault Description ............................................................. ................................................................. ... 102

8.6.2 Handling Procedure............................................................................................................................. 102


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9 Troubleshooting RAB Setup Faults....................................................................................... 103 9.1 About This Chapter ....................................................................................... ............................................... 103

9.2 Definition of RAB Setup Faults .......................................................... ......................................................... 103

9.2.1 RAB Setup Success Rate ................................................................................ .................................... 103

9.2.2 RAB Setup Procedure ................................................................................................ ......................... 103

9.2.3 RAB Setup Failure Scenarios.............................................................................................................. 104

9.3 Possible Causes ............................................................................................................................................ 104

9.4 Troubleshooting RAB Setup Failure ...................................................................................................... ...... 105

9.5 Troubleshooting the Problem of Uu No Response .............................................................. ......................... 107


9.5.2 Fault Handling Procedure ................................................................................................................... 107

9.5.3 Typical Cases ....................................................... ................................................................. .............. 107

9.6 Troubleshooting Increased Traffic Volume .............................. ................................................................. ... 109

9.6.1 Fault Description ............................................................. ................................................................. ... 109 9.6.2 Fault Handling Procedure ................................................................................................................... 109

9.6.3 Typical Cases ....................................................... ................................................................. .............. 109

9.7 Troubleshooting Iub Congestion ................................................................................................. ................. 110



9.7.3 Typical Cases ....................................................... ................................................................. .............. 113

9.8 Troubleshooting Other Congestions ............................................................................................................. 114


9.8.2 Fault Handling Procedure ................................................................................................................... 114 9.8.3 Typical Case 1 ............................................................................................................ ......................... 115

9.8.4 Typical Case 2 ............................................................................................................ ......................... 116

9.9 Troubleshooting the Problem of RAB Setup Not Allowed by the RNC Configuration ............................... 116



9.9.3 Typical Cases ....................................................... ................................................................. .............. 117

9.10 Troubleshooting Transmission Network Faults ................................................................ .......................... 118

9.10.1 Fault Description ........................................................... .............................................................. ...... 118

9.10.2 Fault Handling Procedure ................................................................................................................. 118

9.10.3 Typical Cases ..................................................... ................................................................. .............. 120

9.11 Troubleshooting Physical Channel Faults ................... ................................................................. .............. 121

9.11.1 Fault Description .............................................................................................................. ................. 121

9.11.2 Fault Handling Procedure.................................................................................................................. 121

9.11.3 Typical Cases .......................................... ................................................................. ......................... 122

9.12 Miscellaneous .............................................................. ................................................................. .............. 122



9.12.3 Typical Case 1 .......................................................................................................... ......................... 125

9.12.4 Typical Case 2 .......................................................................................................... ......................... 125


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10 Troubleshooting Call Drops ................................................................................................. 126 10.1 Definition of CDR ....................................................... ................................................................. .............. 126

10.1.1 CDR Formulas .................................................................................................................................. 126

10.1.2 Signaling Procedure for a Call Drop ............................................................. .................................... 127

10.2 Related KPIs for Call Drops .............................................................. ......................................................... 127

10.3 Troubleshooting Procedure ........................................................................................................................ 129

10.4 Troubleshooting Call Drops in a Single Cell or Site .............................................. .................................... 131



10.4.3 Typical Cases ..................................................... ................................................................. .............. 133

10.5 Troubleshooting Call Drops in the Entire Network ........................................................... ......................... 134



10.5.3 Typical Case 1 .......................................................................................................... ......................... 136 10.5.4 Typical Case 2 .......................................................................................................... ......................... 137

10.5.5 Typical Case 3 .......................................................................................................... ......................... 137

11 Troubleshooting Handover Faults ....................................................................................... 139 11.1 About This Chapter........................................... ................................................................. ......................... 139

11.2 Definitions of Handover Faults ........................................................ .......................................................... 139

11.2.1 Handover Success Ratio Formula ................................................................. .................................... 139

11.2.2 Handover Signaling Procedure ........................................................... ............................................... 140

11.3 Handover Procedures ................................................................................................................................. 141

11.4 Troubleshooting Handover Faults ............................... ................................................................. .............. 143


11.4.2 Possible Causes ............................................................. ................................................................. ... 143


11.5 Troubleshooting Faults on Related NEs ........................................... .......................................................... 145


11.5.2 The handover success ratio is low in most of cells, but there is no TOP cell which is quite low.Related Information ..................................................................................................................................... 145


11.6 Troubleshooting Inter-RNC, Inter-MSC, and Inter-RAT Handover Problems ........................................... 146 11.6.1 Fault Description .............................................................................................................. ................. 146

11.6.2 Possible Causes ............................................................. ................................................................. ... 147


11.6.4 Typical Case 1 ......................................... ................................................................. ......................... 149

11.6.5 Typical Case 2 ......................................... ................................................................. ......................... 149

11.6.6 Typical Case 3 ......................................... ................................................................. ......................... 150

11.7 Troubleshooting the Abnormal Handover Caused by Hardware and Transmission Faults......................... 150


11.7.2 Related Information .......................................................................................................................... 150


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11.8 Troubleshooting the Abnormal Handover Caused by Poor Quality of the Air Interface ............................ 151




11.8.4 Typical Cases .......................................... ................................................................. ......................... 152

11.9 Troubleshooting the Abnormal Handover Caused by Incorrect Parameter Settings ................................... 153




11.9.4 Typical Cases .......................................... ................................................................. ......................... 154

11.10 Troubleshooting Congestion in the Target Cell ........................................................................................ 155

11.10.1 Fault Description ............................................................................................................ ................. 155

11.10.2 Possible Causes ........................................................... .............................................................. ...... 155 11.10.3 Fault Handling Procedure ................................................................. ............................................... 155

11.10.4 Typical Cases.................................................... ................................................................. .............. 156

12 Troubleshooting Paging Faults ............................................................................................ 157 12.1 About This Chapter ..................................................................................... ............................................... 157

12.2 Definition of Paging Faults ......................................................................... ............................................... 157

12.3 Related Information.................................................................................................................................... 157

12.3.1 Paging Scenario ................................................................................................................................ 157

12.3.2 Paging Procedure and Performance Counters ................................................................................... 157

12.3.3 Difference Between Paging Success Rates on the RNC and on the CN .................. ......................... 159 12.3.4 Related Paging Handling .................................................................................................................. 160

12.4 Possible Causes .......................................................................................................................................... 160

12.5 Troubleshooting Paging Faults .......................................................... ......................................................... 161


12.5.2 Fault Handling Flowchart ................................................................................................................. 161


12.5.4 Typical Cases 1 ............................ ................................................................. .................................... 164

12.5.5 Typical Cases 2 ............................ ................................................................. .................................... 164

13 Troubleshooting O&M Faults .............................................................................................. 166 13.1 O&M Faults Definition ............................................................................................................. ................. 166

13.2 Context ............................................................. ................................................................. ......................... 166

13.3 Troubleshooting Configuration Data Synchronization Faults .................................................................... 166


13.3.2 Possible Causes ............................................................. ................................................................. ... 166

13.3.3 Troubleshooting Steps .............................................................. ......................................................... 166

13.3.4 Typical Cases ..................................................... ................................................................. .............. 167

13.4 Troubleshooting Counter Abnormalities ...................................................................................... .............. 167



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13.4.2 Possible Causes ............................................................. ................................................................. ... 167


13.4.4 Typical Cases ..................................................... ................................................................. .............. 168

14 Troubleshooting ATM Transmission Faults ..................................................................... 169

14.1 Procedure for Troubleshooting ATM Transmission Faults ........................................................... .............. 169

14.1.1 Determining ATM Transmission Fault Type ..................................................................................... 169

14.1.2 Measures to Troubleshoot ATM Transmission Faults ....................................................................... 169

14.2 Basic knowledge of ATM Transmission ..................................................................................................... 170

14.2.1 Characteristics of ATM Transmission Faults ........................................................... ......................... 170

14.2.2 Introduction to the ATM Layer ............... ................................................................. ......................... 170

14.2.3 ATM Cell Architecture ..................................................................................................... ................. 171

14.2.4 VP/VC Switching .......................................................... .............................................................. ...... 171

14.2.5 ATM VCL ................. .............................................................. .......................................................... 172

14.3 Troubleshooting SAAL Faults ........................................................... ......................................................... 172


14.3.2 Possible Causes ............................................................. ................................................................. ... 173

14.3.3 Troubleshooting Procedure ......................................................................................................... ...... 173


14.4 Troubleshooting AAL2 Path Faults ........................................................................ .................................... 174


14.4.2 Possible Causes ............................................................. ................................................................. ... 175


14.4.4 Troubleshooting Steps .............................................................. ......................................................... 175 14.5 Troubleshooting Packet Loss in ATM Transmission ......................................................... ......................... 176


14.5.2 Possible Causes ............................................................. ................................................................. ... 176



14.6 Troubleshooting Delay and Jitter in ATM Transmission .............................................................. .............. 178


14.6.2 Possible Causes ............................................................. ................................................................. ... 178

14.6.3 Troubleshooting Procedure ......................................................................................................... ...... 178 14.6.4 Troubleshooting Steps .............................................................. ......................................................... 178

14.7 Troubleshooting Packet Error in ATM Transmission .................................. ............................................... 179


14.7.2 Possible Causes ............................................................. ................................................................. ... 179



14.8 Troubleshooting Transient Interruption in ATM Transmission ............................................................... ... 181


14.8.2 Possible Causes ............................................................. ................................................................. ... 181


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14.9 Troubleshooting PVC Faults (ATM layer) ............................. ................................................................. ... 183


14.9.2 Possible Causes ............................................................. ................................................................. ... 183



14.10 Troubleshooting E1T1 Faults (physical layer) ................................ ......................................................... 184

14.10.1 Fault Description ......................................................... .............................................................. ...... 184

14.10.2 Possible Causes ........................................................... .............................................................. ...... 184

14.10.3 Troubleshooting Procedure ....................................................................................................... ...... 184

14.10.4 Troubleshooting Steps ............................................................ ......................................................... 184

14.11 Troubleshooting IMA Faults (physical layer) ....................................................... .................................... 186

14.11.1 Fault Description ............................................................................................................ ................. 186 14.11.2 Possible Causes ........................................................... .............................................................. ...... 186


15 Troubleshooting IP Transmission Faults ........................................................................... 188 15.1 Procedure for Troubleshooting IP Transmission Faults ................................................................ .............. 188

15.1.1 Determining IP Transmission Fault Type ................................................................ .......................... 188

15.1.2 Measures to Troubleshoot IP Transmission Faults .............................................................. .............. 188

15.2 Basic Knowledge of IP Transmission .......................................................... ............................................... 189

15.3 Troubleshooting SCTP Faults ............................................................ ......................................................... 192

15.3.1 Fault Description ........................................................... .............................................................. ...... 192 15.3.2 Possible Causes ............................................................. ................................................................. ... 193



15.3.5 Typical Cases ..................................................... ................................................................. .............. 195

15.4 Troubleshooting IP Path Faults .................................................................................................................. 195


15.4.2 Possible Causes ............................................................. ................................................................. ... 196


15.4.4 Troubleshooting Steps .............................................................. ......................................................... 196 15.4.5 Typical Cases ..................................................... ................................................................. .............. 197

15.5 Troubleshooting IP Pool Faults ......................................................................................... ......................... 198


15.5.2 Possible Causes ............................................................. ................................................................. ... 198



15.5.5 Typical Cases ..................................................... ................................................................. .............. 199

15.6 Troubleshooting IP over FE/GE Interface Disconnection .......................................................................... 200



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15.6.2 Possible Causes ............................................................. ................................................................. ... 200


15.6.4 Troubleshooting IP Layer Faults .............................................................................. ......................... 200

15.6.5 Troubleshooting Data Link Layer Faults ......................................................................... ................. 201

15.6.6 Troubleshooting Physical Layer Faults ................................................................. ............................ 201

15.6.7 Typical Cases ..................................................... ................................................................. .............. 202

15.7 Troubleshooting MP/PPP Link Failure in IP over E1 Mode ........................................................ .............. 203


15.7.2 Possible Causes ............................................................. ................................................................. ... 203


15.7.4 Troubleshooting IP Layer Faults .............................................................................. ......................... 203

15.7.5 Troubleshooting E1T1 Faults (physical layer) ............................................................................ ...... 203

15.7.6 Troubleshooting Data Link Layer Faults ......................................................................... ................. 203

15.8 Troubleshooting Packet Loss in IP Transmission .............................................................. ......................... 204 15.8.1 Fault Description ........................................................... .............................................................. ...... 204

15.8.2 Possible Causes ............................................................. ................................................................. ... 204


15.9 Troubleshooting Delay and Jitter in IP Transmission ........................................................ ......................... 205


15.9.2 Possible Causes ............................................................. ................................................................. ... 206



15.10 Troubleshooting Packet Errors in IP Transmission ........................ .......................................................... 207 15.10.1 Fault Description ......................................................... .............................................................. ...... 207

15.10.2 Possible Causes ........................................................... .............................................................. ...... 207

15.10.3 Troubleshooting Procedure ....................................................................................................... ...... 207


15.11 Troubleshooting Transient Interruption in IP Transmission ............................................ ......................... 208

15.11.1 Fault Description ............................................................................................................ ................. 208

15.11.2 Possible Causes ........................................................... .............................................................. ...... 208

15.11.3 Troubleshooting Procedure ........................................ ............................................................... ...... 208


16 Troubleshooting Faults in SSN Configuration-Free ........................................................ 210 16.1 About This Chapter ..................................................................................... ............................................... 210

16.2 Definition of Faults in SSN Configuration-Free .................................................... .................................... 210

16.3 Related Information.................................................................................................................................... 210

16.4 Troubleshooting the Failed Execution of the ADD UNODEB Command ................................ ................. 212


16.4.2 Possible Causes ............................................................. ................................................................. ... 212


16.5 Troubleshooting the Problem that Automatic SSN Allocation Achieved by the SSN Configuration-FreeAlgorithm Is Inappropriate ............................................................. ................................................................. ... 213


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16.5.2 Possible Causes ............................................................. ................................................................. ... 213


17 Troubleshooting Faults Related to the Inter-Dependence of BBU Uplink Resource Feature.......................................................................................................................................................... 216 17.1 About This Chapter ..................................................................................... ............................................... 216

17.2 Definition of Faults Related to the Inter-Dependence of BBU Uplink Resource Feature .......................... 216

17.3 Troubleshooting Unavailable Cells ...................................................................................................... ...... 216


17.3.2 Possible Causes ............................................................. ................................................................. ... 216


18 Appendix: Common Methods of Collecting Fault Information .................................... 218


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RAN17.1 Troubleshooting Guide 1 Troubleshooting Process and Methods


1

1 Troubleshooting Process and Methods1.1 About this Chapter

This chapter describes the process for troubleshooting, common methods of fault location,and how to get technical support from Huawei.

1.2 Troubleshooting Process

1.2.1 FlowchartFigure 1-1 shows the troubleshooting flowchart.


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Figure 1-1 Troubleshooting flowchart

1.2.2 Collecting and Recording Fault Information

Fault Information to be CollectedWhen a fault occurs, O&M personnel must start troubleshooting by obtaining faultinformation, which serves as a reference. O&M personnel should collect as much faultinformation as possible. The following information must be collected before any operation:

Symptoms, including details and basic data Time, location, and frequency of occurrence Scope and impact Equipment operating status before the fault occurred Operations performed on the equipment before the fault occurred, and the results of these

operations


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Measures taken to deal with the fault, and the results Alarms resulting from the fault Status of board LEDs

Methods of Collecting Fault InformationTo collect fault data, do as follows:

Consult the personnel who reported the fault about symptoms, time, location, andfrequency of the fault.

Consult the O&M personnel about the equipment operating status before the faultoccurred, operations performed on the equipment before the fault occurred, faultsymptoms, and measures taken to deal with the fault and the results.

Observe board LEDs, the O&M subsystem, and the alarm management system to obtaininformation about the status of system software and hardware.

Estimate the impact of the fault by testing services, measuring performance, and tracinginterface messages or signaling messages.

Strategies for Collecting Fault informationStrategies for collecting fault information are as follows:

Do not handle a fault hastily. Collect as much information as possible before attemptingto repair the fault.

Maintain good communication with other departments and O&M personnel of other sites.Ask them for technical support if necessary.

1.2.3 Determining Fault Scope and TypeAfter collecting all available fault information, analyze the fault symptoms, and determine thefault scope and type.

This document describes 11 types of faults, as listed in Table 1-1.

Table 1-1 Faults and scopes

No. Category Fault Type Description

1 HSPA service HSPA service setup failure HSPA service setup failure,instead of a low rate of HSPA

services2 HSUPA rate fault Fluctuating or low HSUPA rate

3 HSDPA rate fault Fluctuating or low HSDPA rate

4 KPI SLC fault Cell access failure

5 RRC connection setupfault

Low RRC connection setupsuccess rate

6 RAB connection setupfault

Low RAB access success rate

7 Call drop rate fault High call drop rate


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No. Category Fault Type Description

8 Handover fault Low handover success rate

9 Paging fault Low paging success rate

10 Operation &Maintenace

Operation & Maintenacefault

Faults of O&M on RAN devices

11 Transmission ATM Transmissionnetwork fault

ATM transmission faults

12 IP Transmission networkfault

IP transmission faults

13 SSNConfiguration-Free

SSN Configuration-Freefaults

The ADD UNODEB commandfails to be executed when theSSN configuration-free

algorithm is enabled.The automatic SSN allocationachieved by the SSNconfiguration-free algorithm isinappropriate.

14 Inter-Dependenceof BBU UplinkResource Feature

Faults Related to theInter-Dependence of BBUUplink Resource Feature

Faults after theInter-Dependence of BBUUplink Resource feature isactivated

1.2.4 Locating the Cause of the FaultTo locate the cause of the fault, first compare and analyze possible causes, and then eliminatecauses that are unlikely or impossible.

Comparison and Interchange Description

O&M personnel can compare the faulty components or symptoms with their normalequivalents to locate faults. Comparison is applied in scenarios where the scope of thefault is small.

If the fault scope and area cannot be determined after the replacement of somecomponents with spare parts, then interchange a component that is suspected of beingfaulty with known good components that are being used in the system. For example,replace a board or optical cable that is suspected faulted with an equivalent item that isknown to be good. Then compare the status before and after the operation to determine ifthe fault was repaired or to further determine the scope and area of the fault. Interchangeis applied in scenarios where the scope of the fault is large.

Application Scenarios

Comparison and interchange are used when faults occur after NE hardware, software or anew feature is introduced that may have caused a service outage.

Instructions


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Use this method to compare the performances and KPIs before and after hardware orsoftware is changed, or a new feature is introduced.

Segment-by-Segment Location Function

A fault may occur at any node in an end-to-end network. Therefore, this method helpslocating the fault quickly.

Application Scenario

Transmission network fault or PS data transmission fault Usage

Locate the fault segment by segment.

Layer-by-Layer Location Function

As specified by the protocol, the upper layer can work properly only when its lowerlayers are working properly. When a fault occurs, all associated layers malfunction. Inaddition, the symptom of a fault may vary if different monitoring methods are used.Therefore, this method helps locating the layer where the fault is generated andfacilitates the troubleshooting.

Application Scenario

Transmission network fault or PS data transmission fault Usage

Locate the fault layer by layer.

1.2.5 TroubleshootingTo repair faults and restore the system, troubleshoot different faults using proper measuresand procedures. Troubleshooting consists of checking cables, replacing boards, modifyingdata configuration, switching over boards, and resetting boards.

1.2.6 Ensuring that System Is RepairedTest the system again after troubleshooting to ensure that the fault is completely repaired.Ensure the system works properly by observing the status of board LEDs and alarminformation, and perform dial tests to ensure that all services are operational.

1.2.7 Recording the Troubleshooting ProcessIt is important to record the troubleshooting process in a way that O&M personnel can use inthe future. When the troubleshooting/repair action is complete, O&M personnel should:

Review the entire troubleshooting process Note key points of the process Summarize methods for improvement

of the system which could avoid recurrence of the faults of the same type.

Ensure notes are recorded in a logbook or other method that O&M personnel will have future access to.


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1.2.8 Contacting Huawei for Technical SupportIf faults are difficult to identify or solve, then prepare the following information, and contactHuawei for technical support.

Step 1 Collect general fault information.

The general information required is as follows:

Full name of the office Contact name and number Time when the fault occurred Detailed symptoms of the fault Version of the host software Measures taken to deal with the fault, and the results Severity and expected repair time

Step 2 Collect fault location information.

Information to be collected is listed according to the related steps.

Step 3 Use the following methods to contact Huawei for technical support:

E-mail: [email protected] Website: http://support.huawei.com

http://support.huawei.com contains contact information for the local office in your region.

mailto:[email protected]://support.huawei.com/http://support.huawei.com/http://support.huawei.com/http://support.huawei.com/mailto:[email protected]


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RAN17.1 Troubleshooting Guide 2 FMA


1

2 FMAAbout This Chapter

This function helps users handle network faults. It includes the following functions: fast faultdiagnosis, fault information collection and hierarchical delimitation. The fault diagnosis andhierarchical delimitation functions analyze faults only within eight hours from the faultrectification to the current time.

The following rights are required to perform the fast fault diagnosis and hierarchicaldelimitation.

− Administrators

− Operators− Users

− Customers that have rights to execute the commands in command groups G2 and G9. The following rights are required to perform the fault information collection.

− Administrators

− Customers that have rights to execute the commands in command groups G2,G8,G9. The following figure shows the fault handling process using this assistant:

Figure 2-1 Fault handling process

− Determine whether services are affected.− Use the fault diagnosis function to identify partial of the faults.


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− Use the hierarchical delimitation function to analyze faults that cannot be fastidentified.

− Use the information collection function to collect logs of faults that cannot beidentified by the preceding two methods, and use the offline analysis tool to analyze

these faults.− Rectify the faults.

− Check that services are recovered.

The Fault Diagnosis, Hierarchical Delimitation, and Information Collection functions cannot beexecuted simultaneously. The COL LOG command cannot be executed when the Fault Diagnosis,Hierarchical Delimitation, or Information Collection function is being executed.

Only one Web LMT can perform an online FMA function at a time.

This function does not support the analysis of an eGBTS.

2.1 Fault OverviewFault overview provides visualized illustration of operating status and fault information ofRNC network.

ContextThis function allows field O&M engineers to quickly obtain fault information and start faulttroubleshooting when a network fault occurs.

Procedure1.On the LMT main page, click FMA . The FMA tab page is displayed.

2.In the Fault Overview window, wait for viewing the KPI trend.

----End

ResultSuccessful operation

The KPI trend chart is displayed in the Fault Overview window.

Table 2-1 Information that O&M engineers can obtain using the fault overview function

Category Details

UMTS KPI Trends in the RRC Trends in the CS RAB Trends in the PS RAB Trends in CS Erlang Trends in PS throughput Trends in the CS call drops Trends in the PS call drops


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Category Details Trends in paging

KPI trend chart KPI and counter change trend chart that

contains three curves illustrating KPIand counter changes in the latest eighthours, in the same hours on the day

before, and in the same hours on thesame day last week, respectively. TheX-coordinate represents themeasurement time (expressed in theform of HH:MM). The Y-coordinaterepresents the counter value in units ofeach counter or the KPI value in

percentages.

NOTE

Performance measurement has two states in shortmeasurement periods: ENABLED andDISABLED . If no counters are measured,

performance measurement is DISABLED .

When fault diagnosis is used to collect performance data, performance datagenerated during a sampling period isnot available if the current measurementstate is different from that used in thesampling period.

For example, if the measurement statewas DISABLED last Wednesday and

changed to ENABLED this Monday,only two curves illustrating KPI andcounter changes in the latest eight hoursof this Wednesday and in the same hoursof this Tuesday are displayed on thetrend chart, with the one for the KPI andcounter changes in the latest eight hoursof last Wednesday missing.

KPI trend value Automatically displays the KPI value orcounter value corresponding to a pointon the KPI and counter change trendcurves when you move the mouse

pointer to that point. Provides KPI filtering on the right of the

fault summary interface to allowviewing the change trend of the selectedKPI.

Unsuccessful operation

A dialog box is displayed with the failure cause.


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2.2 Fault DiagnosisThis function is used to quickly diagnose common network faults, including CS access faults,PS access faults, thereby helping users identify the faulty NE or board. This function can be

used when faults occur and persist at a site and site maintenance personnel cannot directly usethe counters, alarms, and logs for fault analysis.

ContextAccording to the diagnosis rules, this function comprehensively analyzes the counters, alarm,and logs related to the fault and provides analysis reports to users. It helps users performrecovery operations, thereby shortening the fault recovery period.

This function is implemented on the OMU and can be used with tracing and monitoringfunctions on the LMT.

This function is stopped when more than 95% of OMU memory is occupied and this

function occupies more than 500 MB OMU memory. When the OMU CPU usage reaches 100%, the operating systems schedules processes on

the OMU by priority. The initial priority of the fault analysis task using the faultdiagnosing function is set to low. When the CPU usage of this task is lower than theminimum threshold (10%), increase its priority. When the CPU usage of this task ishigher than the minimum threshold (10%), decrease its priority.

When a fault occurs, it is recommended that you use this function to analyze the fault and then run theCOL LOG command to collect logs.

Procedure

1.Optional: Run the SET FMATH command to set the fault diagnosis threshold.

When the default fault diagnosis threshold is not used, run the SET FMATH command to set thethreshold.

To query the specified fault diagnosis threshold, run the LST FMATH command.

2.On the LMT main page, click FMA . The FMA tab page is displayed.

3.Select the fault scenarios requiring fault management on the Fault Diagnosis tab page.

4.Click Start and wait for the diagnosis report.

A folder named by the operation date and time is generated in thebam/version_x/ftp/fma_data/FaultDiagnosis directory each time this function is implemented , forexample, /bam/version_x/ftp/fma_data/FaultDiagnosis /201501010101 . This folder contains foursub-folders which are described in the following table.

Sub-Folder Description

alarm_data Contains the active alarms and cleared alarms forthe last 24 hours.

opt_data Contains the operation data for the last 24 hours.

report Contains the analysis report generated using thefault diagnosis function.

stat_data Contains the performance data for the last 8hours, the corresponding 8 hours in the yesterday,


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Sub-Folder Descriptionand the corresponding 8 hours 7 days ago.

All historical folders are stored in the bam/version_x/ftp/fma_data/FaultDiagnosis directory. Themaximum size of these folders is 500 MB. If the size exceeds 500 MB, the system deletes the earliestfolder. Therefore, you must save required historical analysis results in a timely manner.

Table 2-2 UMTS fault analysis scenario options

Scenario Options Items

KPI RRC Success Rate The number of RRCconnection setup requests is0.

The RRC connection setupsuccess rate is abnormal.

The number of RRCconnection setup requestsdecreases significantly.

CS RAB Setup Success Rate The initial directtransmission flow controlrate of CS services isabnormal.

The Iu-CS SCCP setupsuccess rate is abnormal.

The CS security modesuccess rate is abnormal.

The location update successrate is abnormal.

The CS service rejectionrate is abnormal.

The CS service redirectionrate in a multi-operator corenetwork (MOCN) is

abnormal.

The number of successfulCS RAB setups is 0.

The CS RAB setup successrate is abnormal.

The number of CS RABsetup requests decreasessignificantly.

CS Service Drop Rate The CS service drop rate isabnormal.


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Scenario Options Items

PS RAB Setup Success Rate The initial directtransmission flow controlrate of PS services isabnormal.

The Iu-PS SCCP setupsuccess rate is abnormal.

The PS security modesuccess rate is abnormal.

The RA update success rateis abnormal.

The PS service rejection rateis abnormal.

The attach success rate isabnormal.

The PDP context activationsuccess rate is abnormal.

The PS service redirectionrate in a multi-operator corenetwork (MOCN) isabnormal.

The number of successful

PS RAB setups is 0.The PS RAB setup successrate is abnormal.

The number of PS RABsetup requests decreasessignificantly.

PS Service Drop Rate The PS service drop rate isabnormal.

Paging The paging success rate isabnormal.

Traffic PS throughput The PS throughputdecreases significantly.

CS Erlang The CS Erlang decreasessignificantly.

Transmission Site Break Down A large number of cells areunavailable.

Others Equipment health check Health check on theinterface boards

Health check on theuser-plane boards and


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Scenario Options Itemssubsystems

Health check on the

control-plane boards andsubsystems

Analysis on systemconfiguration errors

Control-plan Iu-CS andIu-PS interface status check

Iur-p interface status check

RNC in Pool Load Sharing The number of RRCconnection setup requests ofthe overflow RNC is 0.

The RRC connection setupsuccess rate of the overflowRNC is abnormal.

The number of successfulCS RAB setups of theoverflow RNC is 0.

The CS RAB setup successrate of the overflow RNC isabnormal.

The CS service drop rate ofthe overflow RNC isabnormal.

The number of successfulPS RAB setups of theoverflow RNC is 0.

The PS RAB setup successrate of the overflow RNC isabnormal.

The PS service drop rate of

the overflow RNC isabnormal.

The CS Erlang of overflowRNC decreasessignificantly.

The PS throughput ofoverflow RNC decreasessignificantly.


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RNC in Pool can be used in different scenarios. The system automatically determines theapplication scenario based on the load sharing type, redundancy type, and host status, asshown in Table 10-3 . You can query the load sharing type by running the LST URNCBASIC command and query the host status by running the DSP UHOSTRNC command.

Table 2-3 RNC in Pool fault analysis scenario options

ScenarioOptions

RNC in PoolLoad Sharing

RNC in PoolRedundancy

RNC in Pool Load Sharingand Redundancy

LoadSharingType=MASTER

LoadSharingType=OVERFLOW

HostStatus=MASTER

HostStatus=BACKUP

LoadSharingType=MASTER andHostStatus=MASTER

LoadSharingType=OVERFLOWandHostStatus=BACKUP

LoadSharingType=OVERFLOWandHostStatus=MASTER

RRCconnectionsetup

√ × √ × √ × √

CS servicesetup

√ × √ × √ × √

CS call drop √ × √ × √ × √

PS servicesetup √ × √ × √ × √

PS call drop √ × √ × √ × √

CS Erlang √ × √ × √ × √

PSthroughput

√ × √ × √ × √

Paging √ × √ × √ × √

A largenumber ofunavailablecells

√ × √ × √ × √

Equipmenthealth check

√ √ √ √ √ √ √

RNC inPool LoadSharing

√ × × × √ × ×

----End


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Result Successful operation

− A new browser window is displayed with the fault analysis report presented on a web page.

Table 2-4 Button Functions

Button Name Description

Save Report When using the IE browser, click this button to save thediagnosis report as an html page. On the saved html page, thelog GUI does not provide the query or filtering function.

When using the FireFox browser, there will be no Save Report button and you can use the save function of the browser itself tosave the diagnosis report.

Download SourceData Download the original data of the diagnosis report that isgenerated by the NE.

A fault diagnosis report covers the following:

Table 2-5 Contents of the diagnosis report

Item Desc

Documents

RAN17.1 Troubleshooting Guide(01)(PDF)-En