4G troubleshooting

eRAN11.1
eRAN Troubleshooting Guide
Issue Draft A
Date 2016-03-07
HUAWEI TECHNOLOGIES CO., LTD.

Copyright © Huawei Technologies Co., Ltd. 2016. All rights reserved.
No part of this document may be reproduced or transmitted in any form or by any means without prior written
consent of Huawei Technologies Co., Ltd.
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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.
Notice
The purchased products, services and features are stipulated by the contract made between Huawei and the
customer. All or part of the products, services and features described in this document may not be within 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 or
representations of any kind, either express or implied.
The information in this document is subject to change without notice. Every effort has been made in the
preparation of this document to ensure accuracy of the contents, but all statements, information, and
recommendations 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: support@huawei.com
Issue Draft A (2016-03-07) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
i

About This Document
Purpose
This document describes how to diagnose and handle eRAN faults. Maintenance engineers
can troubleshoot the following faults by referring to this document:
l Faults reflected in user complaints
l Faults found during routine maintenance
l Sudden faults
l Faults indicated by alarms
Product Versions
The following table lists the product versions related to this document.
Product Name Solution Version Product Version
BTS3900 l SRAN11.1
l eRAN11.1
V100R011C10
BTS3900A
BTS3900L
BTS3900AL
BTS3202E
BTS3911E
DBS3900 l SRAN11.1
l eRAN11.1
l eRAN TDD 11.1
DBS3900 LampSite
Intended Audience
This document is intended for:
l System engineers
eRAN11.1
eRAN Troubleshooting Guide About This Document
ii

l Site maintenance engineers
Organization
1 Change Description
This chapter describes the changes in eRAN Troubleshooting Guide.
2 Troubleshooting Process
This chapter describes the general troubleshooting process and methods.
3 Common Maintenance Functions
This chapter describes common maintenance functions that are used to analyze and handle
faults. It also explains or provides references on how to use the functions.
4 Troubleshooting Access Faults
This chapter describes how to diagnose and handle access faults.
5 Troubleshooting Intra-RAT Handover Faults
This chapter describes how to diagnose and handle intra-RAT handover faults. RAT is short
for radio access technology.
6 Troubleshooting Service Drops
This chapter describes the method and procedure for troubleshooting service drops in the
Long Term Evolution (LTE) system. It also provides the definitions of service drops and
related key performance indicator (KPI) formulas.
7 Troubleshooting Inter-RAT Handover Faults
This section defines inter-RAT handover faults, describes handover principles, and provides
the fault handling method and procedure.
8 Troubleshooting Rate Faults
This chapter provides definitions of faults related to traffic rates and describes how to
troubleshoot low uplink/downlink UDP/TCP rates and rate fluctuations. UDP is short for User
Datagram Protocol, and TCP is short for Transmission Control Protocol.
9 Troubleshooting Cell Unavailability Faults
This chapter defines cell unavailability faults and provides a troubleshooting method.
10 Troubleshooting IP Transmission Faults
This section defines IP transmission faults and describes how to troubleshoot IP transmission
faults.
11 Troubleshooting Application Layer Faults
This chapter describes the definitions of application layer faults and the troubleshooting
method.
12 Troubleshooting Transmission Synchronization Faults
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This chapter describes how to troubleshoot transmission synchronization faults. The faults of
this type include the clock reference problem, IP clock link fault, system clock unlocked fault,
base station synchronization frame number error, or time synchronization failure.
13 Troubleshooting Transmission Security Faults
This chapter describes how to troubleshoot transmission security faults.
14 Troubleshooting RF Unit Faults
This chapter describes the method and procedure for troubleshooting radio frequency (RF)
unit faults in the Long Term Evolution (LTE) system.
15 Troubleshooting License Faults
This chapter describes how to diagnose and handle license faults.
16 Wireless Fault Management
Generally, when a radio performance fault or network-level performance fault occurs, OM
engineers cannot quickly delimit the fault range and recover the service by resetting,
powering off, or replacing corresponding boards. To address this issue, the FMA provides a
radio performance fault analysis function, helping OM engineers quickly find the method of
recovering services. Using this function, the troubleshooting efficiency is improved.
17 Collecting the Information Required for Fault Location
When faults cannot be rectified by referring to this document, collect fault information for
Huawei technical support to quickly troubleshoot the faults. This section describes how to
collect fault information.
Conventions
Symbol Conventions
The symbols that may be found in this document are defined as follows.
Symbol Description
Indicates an imminently hazardous situation which, if not
avoided, will result in death or serious injury.
Indicates a potentially hazardous situation which, if not
avoided, could result in death or serious injury.
avoided, may result in minor or moderate injury.
avoided, could result in equipment damage, data loss,
performance deterioration, or unanticipated results.
NOTICE is used to address practices not related to personal
injury.
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Symbol Description
Calls attention to important information, best practices and
tips.
NOTE is used to address information not related to
personal injury, equipment damage, and environment
deterioration.
General Conventions
The general conventions that may be found in this document are defined as follows.
Convention Description
Times New Roman Normal paragraphs are in Times New Roman.
Boldface Names of files, directories, folders, and users are in
boldface. For example, log in as user root.
Italic Book titles are in italics.
Courier New Examples of information displayed on the screen are in
Courier New.
Command Conventions
The command conventions that may be found in this document are defined as follows.
Boldface The keywords of a command line are in boldface.
Italic Command arguments are in italics.
[ ] Items (keywords or arguments) in brackets [ ] are optional.
{ x | y | ... } Optional items are grouped in braces and separated by
vertical bars. One item is selected.
[ x | y | ... ] Optional items are grouped in brackets and separated by
vertical bars. One item is selected or no item is selected.
{ x | y | ... }* Optional items are grouped in braces and separated by
vertical bars. A minimum of one item or a maximum of all
items can be selected.
[ x | y | ... ]* Optional items are grouped in brackets and separated by
vertical bars. Several items or no item can be selected.
GUI Conventions
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The GUI conventions that may be found in this document are defined as follows.
Boldface 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.
Keyboard Operations
The keyboard operations that may be found in this document are defined as follows.
Format Description
Key Press the key. For example, press Enter and press Tab.
Key 1+Key 2 Press the keys concurrently. For example, pressing Ctrl
+Alt+A means the three keys should be pressed
concurrently.
Key 1, Key 2 Press the keys in turn. For example, pressing Alt, A means
the two keys should be pressed in turn.
Mouse Operations
The mouse operations that may be found in this document are defined as follows.
Action Description
Click Select and release the primary mouse button without
moving the pointer.
Double-click Press the primary mouse button twice continuously and
quickly without moving the pointer.
Drag Press and hold the primary mouse button and move the
pointer to a certain position.
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Contents
About This Document.....................................................................................................................ii
1 Change Description.......................................................................................................................1
2 Troubleshooting Process..............................................................................................................2
2.1 General Troubleshooting Process...................................................................................................................................3
2.2 Troubleshooting Methods...............................................................................................................................................4
2.2.1 Data Backup................................................................................................................................................................ 4
2.2.2 Fault Information Collection....................................................................................................................................... 4
2.2.3 Determining the Fault Scope and Type....................................................................................................................... 6
2.2.4 Identifying Fault Causes..............................................................................................................................................8
2.2.5 Rectifying the Fault..................................................................................................................................................... 8
2.2.6 Checking Whether Faults Have Been Rectified..........................................................................................................8
2.2.7 Contacting Huawei Technical Support........................................................................................................................ 9
3 Common Maintenance Functions............................................................................................ 11
3.1 User Tracing................................................................................................................................................................. 12
3.2 Interface Tracing...........................................................................................................................................................12
3.3 Comparison/Interchange...............................................................................................................................................12
3.4 Switchover/Reset..........................................................................................................................................................12
3.5 MBTS Emergency OM Channel.................................................................................................................................. 13
3.5.1 Overview................................................................................................................................................................... 13
3.5.2 Application Scenarios................................................................................................................................................14
3.5.3 Emergency OM Channel Establishment....................................................................................................................16
3.5.4 Function Description................................................................................................................................................. 21
3.5.5 Troubleshooting.........................................................................................................................................................25
3.5.6 Example of Using the Proxy MML Function............................................................................................................25
3.5.7 Other Operations........................................................................................................................................................30
3.6 Remote Query of Services on Disconnected eNodeBs.................................................................................................30
3.6.1 Overview................................................................................................................................................................... 31
3.6.2 Application Scenarios................................................................................................................................................31
3.6.3 Function Description................................................................................................................................................. 31
3.6.4 Troubleshooting.........................................................................................................................................................34
4 Troubleshooting Access Faults................................................................................................. 35
4.1 Definitions of Access Faults.........................................................................................................................................36
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4.2 Background Information...............................................................................................................................................36
4.3 Troubleshooting Method...............................................................................................................................................38
4.4 Troubleshooting Access Faults Caused by Incorrect Parameter Configurations......................................................... 41
4.5 Troubleshooting Access Faults Caused by Radio Environment Abnormalities...........................................................47
5 Troubleshooting Intra-RAT Handover Faults....................................................................... 52
5.1 Definitions of Intra-RAT Handover Faults...................................................................................................................53
5.4 Troubleshooting Intra-RAT Handover Faults Caused by Hardware Faults..................................................................56
5.5 Troubleshooting Intra-RAT Handover Faults Caused by Incorrect Data Configurations............................................ 59
5.6 Troubleshooting Intra-RAT Handover Faults Caused by Target Cell Congestion....................................................... 61
5.7 Troubleshooting Intra-RAT Handover Faults Caused by Poor-Quality Uu Interface.................................................. 63
6 Troubleshooting Service Drops................................................................................................67
6.1 Definitions of Service Drop Faults...............................................................................................................................69
6.4 Troubleshooting Radio Faults.......................................................................................................................................74
6.5 Troubleshooting Transmission Faults...........................................................................................................................75
6.6 Troubleshooting Congestion.........................................................................................................................................76
6.7 Troubleshooting Handover Failures............................................................................................................................. 77
6.8 Troubleshooting MME Faults.......................................................................................................................................78
7 Troubleshooting Inter-RAT Handover Faults....................................................................... 81
7.1 Definitions of Inter-RAT Handover Faults...................................................................................................................83
7.4 Troubleshooting Inter-RAT Handover Faults Due to Hardware Faults........................................................................87
7.5 Troubleshooting Inter-RAT Handover Faults Due to Poor UE Capabilities................................................................ 90
7.6 Troubleshooting Inter-RAT Handover Faults Due to Incorrect Parameter Configurations..........................................93
7.7 Troubleshooting Inter-RAT Handover Faults Due to Target Cell Congestion............................................................. 96
7.8 Troubleshooting Inter-RAT Handover Faults Due to Incorrect EPC Configurations...................................................97
7.9 Troubleshooting Inter-RAT Handover Faults Due to Radio Environment Abnormalities...........................................98
7.10 Troubleshooting Inter-RAT Handover Faults Due to Abnormal UEs...................................................................... 101
8 Troubleshooting Rate Faults................................................................................................... 103
8.1 Definitions of Rate Faults...........................................................................................................................................104
8.2 Background Information.............................................................................................................................................104
8.3 Troubleshooting Abnormal Single-UE Rates.............................................................................................................107
8.4 Troubleshooting Abnormal Multi-UE Rates.............................................................................................................. 113
9 Troubleshooting Cell Unavailability Faults........................................................................ 116
9.1 Definitions of Cell Unavailability Faults....................................................................................................................117
9.2 Background Information.............................................................................................................................................117
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9.3 Troubleshooting Method.............................................................................................................................................118
9.4 Troubleshooting Cell Unavailability Faults Due to Incorrect Data Configuration.................................................... 120
9.5 Troubleshooting Cell Unavailability Faults Due to Abnormal Transport Resources.................................................122
9.6 Troubleshooting Cell Unavailability Faults Due to Abnormal RF Resources........................................................... 123
9.7 Troubleshooting Cell Unavailability Faults Due to Limited Capacity or Capability.................................................126
9.8 Troubleshooting Cell Unavailability Faults Due to Faulty Hardware........................................................................127
10 Troubleshooting IP Transmission Faults........................................................................... 130
10.1 Definitions of IP Transmission Faults...................................................................................................................... 131
10.2 Background Information...........................................................................................................................................131
10.3 Troubleshooting Method...........................................................................................................................................131
10.4 Troubleshooting the Physical Layer......................................................................................................................... 132
10.5 Troubleshooting the Data Link Layer.......................................................................................................................135
10.6 Troubleshooting the IP Layer................................................................................................................................... 137
11 Troubleshooting Application Layer Faults........................................................................ 139
11.1 Definitions of Application Layer Faults...................................................................................................................140
11.4 Troubleshooting the SCTP Link...............................................................................................................................141
11.5 Troubleshooting the IP Path......................................................................................................................................145
11.6 Troubleshooting the OM Channel............................................................................................................................ 146
12 Troubleshooting Transmission Synchronization Faults................................................. 149
12.1 Definitions of Transmission Synchronization Faults................................................................................................150
12.3 Troubleshooting Specific Transmission Synchronization Faults............................................................................. 150
13 Troubleshooting Transmission Security Faults................................................................ 154
13.1 Definitions of Transmission Security Faults............................................................................................................ 155
13.3 Troubleshooting Specific Transmission Security Faults.......................................................................................... 156
14 Troubleshooting RF Unit Faults...........................................................................................165
14.1 Definitions of RF Unit Faults................................................................................................................................... 166
14.4 Troubleshooting VSWR Faults.................................................................................................................................172
14.5 Troubleshooting RTWP Faults................................................................................................................................. 174
14.6 Troubleshooting ALD Link Faults........................................................................................................................... 180
15 Troubleshooting License Faults............................................................................................182
15.1 Definitions of License Faults....................................................................................................................................183
15.4 Troubleshooting License Faults That Occur During License Installation................................................................184
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15.5 Troubleshooting License Faults That Occur During Network Running...................................................................187
15.6 Troubleshoot License Faults That Occur During Network Adjustment...................................................................189
16 Wireless Fault Management..................................................................................................193
16.1 Overview of Wireless Fault Management................................................................................................................ 194
16.2 Starting Wireless Fault Management........................................................................................................................194
16.2.1 (Optional) Setting Parameters for Performance Fault Analysis............................................................................ 194
16.2.2 Starting Fault Overview.........................................................................................................................................195
16.2.3 Starting Fault Delimitation.................................................................................................................................... 200
16.2.4 Starting Information Collection.............................................................................................................................204
16.3 Appendix.................................................................................................................................................................. 204
16.3.1 KPIs Supported by Wireless Fault Management and Their Calculation Formulas...............................................204
17 Collecting the Information Required for Fault Location.................................................207
Index................................................................................................................................................223
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1Change Description
This chapter describes the changes in eRAN Troubleshooting Guide.
Draft A (2016-03-7)
This is a draft.
Compared with 01 (2015-12-31) of V100R010C10, this issue includes the following new
information.
Topic Change History
3.6 Remote Query of Services on
Disconnected eNodeBs
Added the function of querying resources and
services on neighboring eNodeBs based on X2
interface tracing when neighboring eNodeBs are
disconnected from the OSS.
Compared with 01 (2015-12-31) of V100R010C10, this issue includes the following changes.
Topic Change History
17 Collecting the Information
Required for Fault Location
Added the method of using WebNIC to collect fault
location information in cell DT tracing and
spectrum detection.
No information in 01 (2015-12-31) of V100R010C10 is deleted from this issue.
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eRAN Troubleshooting Guide 1 Change Description
1

2Troubleshooting Process
About This Chapter
This chapter describes the general troubleshooting process and methods.
2.1 General Troubleshooting Process
This section describes the troubleshooting procedure.
2.2 Troubleshooting Methods
This section describes each step in the troubleshooting procedure in detail.
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2.1 General Troubleshooting Process
This section describes the troubleshooting procedure.
Figure 2-1 shows the troubleshooting flowchart.
Figure 2-1 Troubleshooting flowchart
Table 2-1 details each step of the troubleshooting procedure.
Table 2-1 Steps in the troubleshooting procedure
No. Step Remarks
1 2.2.1 Data Backup Data to be backed up includes the database, alarm
information, and log files.
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No. Step Remarks
2 2.2.2 Fault
Information Collection
Fault information is essential to troubleshooting.
Therefore, maintenance personnel are advised to
collect as much fault information as possible.
3 2.2.3 Determining the
Fault Scope and Type
Determine the fault scope and type based on the
symptoms.
4 2.2.4 Identifying Fault
Causes
Identify the fault causes based on the fault information
and symptom.
5 2.2.5 Rectifying the
Fault
Take appropriate measures or steps to rectify the fault.
6 2.2.6 Checking
Whether Faults Have
Been Rectified
Verify whether the fault is rectified.
If the fault is rectified, the troubleshooting process
ends. If the fault persists, check whether this fault falls
in another fault type.
7 2.2.7 Contacting
Huawei Technical
Support
If the fault type cannot be determined, or the fault
cannot be rectified, contact Huawei technical support.
2.2 Troubleshooting Methods
This section describes each step in the troubleshooting procedure in detail.
2.2.1 Data Backup
To ensure data security, first save onsite data and back up related databases, alarm
information, and log files during troubleshooting.
For details about data to be backed up and how to back up data, see eRAN Routine
Maintenance Guide.
2.2.2 Fault Information Collection
Fault information is essential to troubleshooting. Therefore, maintenance personnel should
collect fault information as much as possible.
Fault Information to Be Collected
Before rectifying a fault, collect the following information:
l Fault symptom
l Time, location, and frequency
l Scope and impact
l Equipment running status before the fault occurs
l Operations performed on the equipment before the fault occurs, and the results of these
operations
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l Measures taken to deal with the fault, and the results
l Alarms and correlated alarms when the fault occurs
l Board indicator status when the fault occurs
Fault Information Collection Methods
The methods for collecting fault information are as follows:
l Consult the person who reports the fault about the symptom, time, location, and
frequency of the fault.
l Consult maintenance personnel about the equipment running status, fault symptom,
operations performed before the fault occurs, and measures taken after the fault occurs
and the effect of these measures.
l Observe the board indicator, operation and maintenance (OM) system, and alarm
management system to obtain the software and hardware running status.
l Estimate the scope and impact of the fault by means of service demonstration,
performance measurement, and interface or signaling tracing.
Fault Information Collection Skills
The following are skills in collecting fault information:
l Do not handle a fault hastily. Collect as much information as possible before rectifying
the fault.
l Keep good liaison with maintenance personnel of other sites. Resort to them for
technical support if necessary.
Fault Information Classification
Table 2-2 Fault information types
Type Attrib
ute
Description
Original
information
Definiti
on
Original information includes the fault information reflected in
user complaints, fault notifications from other offices,
exceptions detected in maintenance, and the information
collected by maintenance personnel through different channels
in the early period when the fault is found. Original information
is important for fault locating and analysis.
Functio
n
Original information is used to determine the fault scope and
fault category. Original information helps narrow the fault scope
and locate the faults in the initial stage of troubleshooting.
Original information can also help troubleshoot other faults,
especially trunk faults.
Referen
ce
None
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Type Attrib
ute
Description
Alarm
information
Definiti
on
Alarm information is the output of the eNodeB alarm system. It
relates to the hardware, links, trunk, and CPU load of the
eNodeB, and includes the description of faults or exceptions,
fault causes, and handling suggestions. Alarm information is a
key element for fault locating and analysis.
Functio
n
Alarm information is specific and complete; therefore, it is
directly used to locate the faulty component or find the fault
cause. In addition, alarm information can also be used with other
methods to locate a fault.
Referen
ce
For details about how to use the alarm system, see U2000 Online
Help. For detailed information about each alarm, see eNodeB
Alarm Reference.
Indicator
status
Definiti
on
Board indicators indicate the running status of boards, circuits,
links, optical channels, and nodes. Indicator status information is
also a key element for fault locating and analysis.
Functio
n
By analyzing indicator status, you can roughly locate faulty
components or fault causes that facilitate subsequent operations.
Generally, indicator status information is combined with alarm
information for locating faults.
Referen
ce
For the description of indicator status, see associated hardware
description manuals.
Performance
counter
Definiti
on
Performance counters are statistics about service performance,
such as statistics about service drops and handovers. They help
find out causes of service faults so that measures can be taken in
a timely manner to prevent such faults.
Functio
n
Performance counters are used with signaling tracing and
signaling analysis to locate causes of service faults such as a
high service drop rate, low handover success rate, and service
exception. They are generally used for the key performance
indicator (KPI) analysis and performance monitoring of the
entire network.
Referen
ce
For details about the usage of performance counters, see U2000
Online Help. For the definitions of each performance counter,
see eNodeB Performance Counter Reference.
2.2.3 Determining the Fault Scope and Type
Based on the fault symptom, determine the fault type.
In this document, faults are classified according to symptoms. eRAN faults are classified into
service faults and equipment faults.
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Service Faults
Service faults are further classified into the following types:
l Access faults
– User access fails.
– The access success rate is low.
l Handover faults
– The intra-frequency handover success rate is low.
– The inter-frequency handover success rate is low.
l Service drop faults
– Service drops occur during handovers.
– Services are unexpectedly released.
l Inter-RAT interoperability faults
Inter-RAT handovers cannot be normally performed.
l Rate faults
– Data rates are low.
– There is no data rate.
– Data rates fluctuate.
Equipment Faults
Equipment faults are further classified into the following types:
l Cell faults
– Cell setup fails.
– Cell activation fails.
l Operation and maintenance channel (OMCH) faults
– The OMCH is interrupted or fails intermittently.
– The CPRI link does not work properly.
– The S1/X2/SCTP/IPPATH links do not work properly.
– IP transport is abnormal.
l Clock faults
– The clock source is faulty.
– The IP clock link is faulty.
– The system clock is out of lock.
l Security faults
– The IPSec tunnel is abnormal.
– SSL negotiation is abnormal.
– Digital certificate processing is abnormal.
l Radio frequency faults
– The standing wave is abnormal.
– The received total wideband power (RTWP) on the RX channel is abnormal.
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– The antenna line device (ALD) link does not work properly.
l License faults
– License installation fails.
– License modification fails.
2.2.4 Identifying Fault Causes
Fault locating is a process of finding the fault causes from many possible causes. By
analyzing and comparing all possible causes and then excluding impossible factors, you can
determine the specific fault causes.
Locating Equipment Faults
Locating equipment faults is easier than locating service faults. Though there are many types
of equipment faults, the fault scope is relatively narrow. Equipment faults are generally
indicated by the indicator status, alarms, and error messages. Based on the indicator status
information, alarm handling suggestions, or error messages, users can rectify most equipment
faults.
Locating Service Faults
The methods for locating different types of service faults are as follows:
l Access faults: Check the S1 interface and Uu interface. Locate transmission faults
segment by segment. Then, determine whether faults occur in the eRAN based on the
interface conditions. If so, proceed to locate specific faults.
l Rate faults: Check whether there are access faults. If there are access faults, locate
specific faults by using the previous methods. Then, check the traffic on the IP path to
determine fault points.
l Handover faults: Start signaling tracing and determine fault points according to the
signaling flow.
For instructions on fault locating and analysis, see 3 Common Maintenance Functions.
2.2.5 Rectifying the Fault
To troubleshoot a fault, take proper measures to eliminate the fault and restore the system,
including checking and repairing cables, replacing boards, modifying configuration data,
switching over the system, and resetting boards. Maintenance personnel need to clear
different faults using proper methods.
After the fault is cleared, be sure to perform the following:
l Perform testing to confirm that the fault has been rectified.
l Record the troubleshooting process and key points.
l Summarize measures of preventing or decreasing such faults. This helps to prevent
similar faults from occurring in the future.
2.2.6 Checking Whether Faults Have Been Rectified
Check the equipment running status, observe the board indicator status, and query alarm
information to verify that the system is running properly. Perform testing to confirm that the
fault has been cleared and that services return to normal.
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2.2.7 Contacting Huawei Technical Support
If the fault type cannot be determined, or the fault cannot be cleared, contact Huawei technical
support.
If you need to contact Huawei technical support during troubleshooting, collect necessary
information in advance.
Collecting General Fault Information
General fault information includes the following:
l Name of the office
l Name and phone number of the contact person
l Time when the fault occurs
l Detailed description of the fault symptoms
l Host software version of the equipment
l Measures taken after the fault occurs and the result
l Severity of the fault and the time required for rectifying the fault
Collecting Fault Location Information
When a fault occurs, collect the following information:
l One-click logs of the main control board (Applicable to 3900 series base stations only)
l One-click logs of baseband boards (Applicable to 3900 series base stations only)
l One-click logs of RRUs (Applicable to 3900 series base stations only)
l One-click logs (Applicable to BTS3202E and BTS3911E only)
l Alarm information
l KPI data of the entire network
l Intelligent field test system (IFTS) tracing
l Cell drive test (DT) tracing
l SCTP link tracing
l Signaling tracing on interfaces
l eNodeB configuration information
l U2000 self-organizing network (SON) logs
l U2000 adaptation logs
l U2000 software module management logs
For details about how to collect fault information, see 3900 Series Base Station LMT User
Guide, eNodeB Performance Monitoring Reference, eRAN Routine Maintenance Guide, and
U2000 Online Help.
Contacting Huawei Technical Support
The following lists the contact information of Huawei technical support:
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l Contact the technical support personnel in the local Huawei office.
l Email: support@huawei.com
l Website: http://support.huawei.com
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3Common Maintenance Functions
About This Chapter
This chapter describes common maintenance functions that are used to analyze and handle
faults. It also explains or provides references on how to use the functions.
3.1 User Tracing
User tracing is a function that traces all messages of a user in sequence over standard and
internal interfaces, traces internal status of the user equipment (UE), and displays the tracing
results on the screen.
3.2 Interface Tracing
Interface tracing is a function that traces all messages within a period in sequence on a
standard or internal interface and displays them on the screen.
3.3 Comparison/Interchange
Comparison and interchange are used to locate faults in a piece or pieces of equipment.
3.4 Switchover/Reset
Switchover helps identify whether the originally active equipment is faulty or whether the
active/standby relationship is normal. Reset is used to identify whether software running
errors exist.
3.5 MBTS Emergency OM Channel
This chapter describes the functions, application scenarios, and usage methods of MBTS
emergency OM channel.
3.6 Remote Query of Services on Disconnected eNodeBs
This section describes the function, application scenarios, and methods of remotely querying
services on disconnected eNodeBs based on X2 interface tracing.
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3.1 User Tracing
User tracing is a function that traces all messages of a user in sequence over standard and
internal interfaces, traces internal status of the user equipment (UE), and displays the tracing
results on the screen.
User tracing has the following advantages:
l Real-time
l Able to trace the user over all standard interfaces
l Usable when traffic is heavy
l Applicable in various scenarios, for example, call procedure analysis and VIP user
tracing
User tracing is usually used to diagnose call faults that can be reproduced. For details about
how to perform user tracing, see the online help for the operation and maintenance system.
3.2 Interface Tracing
Interface tracing is a function that traces all messages within a period in sequence on a
standard or internal interface and displays them on the screen.
Interface tracing has the following advantages:
l Real-time
l Complete: All messages within a period on an interface can be traced.
l Able to trace link management messages
Interface tracing applies in scenarios where user equipment (UEs) involved are uncertain. For
example, this function can be used to diagnose the cause for a low success rate of radio
resource control (RRC) connection setup at a site. For details about how to perform interface
tracing, see the online help for the operation and maintenance system.
3.3 Comparison/Interchange
Comparison and interchange are used to locate faults in a piece or pieces of equipment.
Comparison is a function used to locate a fault by comparing the faulty component or fault
symptom with a functional component or normal condition, respectively. Interchange is a
function used to locate a fault by interchanging a possibly faulty component with a functional
component and comparing the running status before and after the interchange.
Comparison usually applies in scenarios with a single fault. Interchange usually applies in
scenarios with complicated faults.
3.4 Switchover/Reset
Switchover helps identify whether the originally active equipment is faulty or whether the
active/standby relationship is normal. Reset is used to identify whether software running
errors exist.
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Switchover switching of the active and standby roles of equipment so that the standby
equipment takes over services. Comparing the running status before and after the switchover
helps identify whether the originally active equipment is faulty or whether the active/standby
relationship is normal. Reset is a means to manually restart part of or the entire equipment. It
is used to identify whether software running errors exist.
Switchover and reset can only be emergency resorts. Exercise caution when using them,
because:
l Compared with other functions, switchover and reset can only be auxiliary means for
fault locating.
l Because software runs randomly, a fault is usually not reproduced in a short period after
a switchover or reset. This hides the fault, which causes risks in secure and stable
running of the equipment.
l Resets might interrupt services. Improper operations may even cause collapse. The
interruption and collapse have a severe impact on the operation of the system.
3.5 MBTS Emergency OM Channel
This chapter describes the functions, application scenarios, and usage methods of MBTS
emergency OM channel.
3.5.1 Overview
If the OM channel of one mode in a separate-MPT MBTS fails, the available OM channels of
other modes can be used for remote troubleshooting on the LMT for the base station whose
OM channel is faulty. In this way, unnecessary site visit is avoided and fault location becomes
efficient and cost-effective.
Function Introduction
An emergency OM channel can be established between a GBTS and an eGBTS/NodeB/
eNodeB, or among the eGBTS, NodeB, and eNodeB, as shown in Figure 3-1 and Figure 3-2.
A GBTS can only serve as the proxy base station instead of the target base station. A base
station whose OM channel is normal can serve as the proxy base station; while a base station
whose OM channel is faulty is the target base station.
Figure 3-1 Emergency OM channel between a GBTS and an eGBTS/NodeB/eNodeB
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Figure 3-2 Emergency OM channel among eGBTS, NodeB, and eNodeB
With an emergency OM channel, the Proxy MML and Proxy PNP Trace functions can be used
on the proxy base station. For details about the functions, see 3.5.4 Function Description.
Security About the Emergency OM Channel
If the security requirement of the target base station is higher than that of the proxy base
station, using the emergency OM channel lowers the security of the target base station. For
example, if a NodeB and an eNodeB serve as the proxy and target base stations, respectively
and the OM channel encryption mechanism of the eNodeB is higher than that of the NodeB,
using the emergency OM channel lowers the security of the eNodeB.
3.5.2 Application Scenarios
This chapter describes the application scenarios for MBTS emergency OM channel.
Read the following notes before establishing an emergency OM channel:
l The proxy base station and the target base station support different transport protocol
stacks. Table 3-1 shows the transport protocol stacks supported by the proxy base station
and the target base station.
Table 3-1 Transport protocol stacks supported by the proxy and target base stations
Transport Protocol
Stack
Is Supported by Proxy
Base Station?
Is Supported by Target
Base Station?
TDM for GBTS Yes No
IP over E1 for GBTS/
eGBTS/NodeB
Yes Yes
IP over Ethernet for
GBTS/NodeB/eNodeB
Yes Yes
ATM for NodeB Yes Yes
l Either separate transmission or co-transmission can be used by the proxy and target base
stations. In the co-transmission scenario, both panel and backplane interconnections can
be used.
l The proxy and target base stations can be configured with either one or multiple BBUs.
At present, a maximum of two BBUs are supported.
l Table 3-2 describes the MPT types and modes of the proxy and target base stations,
which can be combined to support the emergency OM channel establishment.
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Table 3-2 Combination of MPT types and modes of the proxy and target base stations
MPT Type and Mode of Proxy Base
Station
MPT Type and Mode of Target Base
Station
GTMU l WMPT
l LMPT
l UMPT_U
l UMPT_L
l UMPT_UL
WMPT l LMPT
l UMPT_L
l UMPT_GL
LMPT l WMPT
l UMPT_U
l UMPT_GU
UMPT_G l WMPT
l LMPT
l UMPT_UL
l UMPT_U
l UMPT_L
UMPT_U l LMPT
l UMPT_GL
l UMPT_G
l UMPT_L
UMPT_L l WMPT
l UMPT_GU
l UMPT_G
l UMPT_U
UMPT_GU l LMPT
l UMPT_L
UMPT_GL l WMPT
l UMPT_U
UMPT_UL UMPT_G
When the emergency OM channel is enabled, the OM data is transmitted to the target base
station through the OM channel of the proxy base station. The data rate on the OM channel of
the GBTS is less than 64 kbit/s. Therefore, before enabling the emergency OM channel,
ensure that the no congestion occurs on the OM channel of the proxy base station. Otherwise,
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the emergency OM channel cannot work or services of the proxy base station will not be
affected.
3.5.3 Emergency OM Channel Establishment
This section describes how to establish an emergency OM channel and verify establishment
results.
Establishment Method
To establish an emergency OM channel, the proxy base station must be selected first and then
the information of the target base station must be correctly configured.
1. Select the proxy base station.
The methods of confirming which base station can be selected as the proxy base stations
are as follows
– If the base stations of all modes in a multi-mode base station are configured with
the same DID, the U2000 automatically matches the proxy base station to the target
base station. For example, MBTS-GUMUX+L3 separate-MPT base stations are in
the same frame in the Main Topology window.
Figure 3-3 Automatically matching the proxy base station to target base station
– You can select the proxy base station according to the site planning of the operator,
for example, by identifying the base stations with the same site name.
If the GBTS serves as the proxy base station, you need to establish the emergency
OM channel on the GBSC LMT. If the eGBTS/NodeB/eNodeB serves as the proxy
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base station, you need to establish the emergency OM channel on the LMT of the
corresponding base station.
Take the GBTS as an example. Start the GBSC LMT on the U2000 by right-
clicking the GBTS serving as the proxy base station and then choosing
Maintenance Client from the shortcut menu, as shown in Figure 3-4.
Figure 3-4 Selecting the proxy base station
2. Establish the emergency OM channel.
Figure 3-5 and Figure 3-6 show how to establish the emergency OM channel on the
GBSC LMT and on the LMT of eGBTS/NodeB/eNodeB, respectively.
Figure 3-5 Emergency OM channel establishment on the GBSC LMT
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Figure 3-6 Emergency OM channel establishment on the LMT of eGBTS/NodeB/
eNodeB (taking the eGBTS as an example)
Figure 3-7 shows the parameter settings in different configuration scenarios.
Figure 3-7 Parameter settings of GBSC
SN Configuration Scenario
1 Single-BBU
2 Two-BBU (in multi-BBU scenario) with
the subrack number of the target base
station being 0
3 Two-BBU (in multi-BBU scenario) with
the subrack number of the target base
station being 1
Configuration notes are as follows:
– In single-BBU scenario, the following information of the target base station must be
configured.
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n Main Control Board Sot No.: This parameter can be set to 6 or 7.
n User Name and Password: These two parameters specify the user name and
password for logging in to the LMT. Note that the user name and password
must have been granted administrator permissions. By default, the user name
is admin and the password is hwbs@com. Both are case-sensitive.
NOTE
If they have been changed, set the parameters to the new ones.
– In multi-BBU scenario, in addition to the preceding information in single-BBU
scenario, the inter-BBU topology information of base stations must also be
configured.
n Main Control Board Subrack No.: This parameter specifies the number of
the BBU housing the main control board of the target base station. This
parameter is set to 0 and 1 if the main control board is configured in the root
BBU and leaf BBU, respectively.
n If the preceding parameter is set to 1, parameters in the CTRLLNK MO need
to be configured.
○ CTPLLNK Parent Node Slot No.: This parameter is set to the number
of the slot where the parent-node UMPT locates in UMPT
interconnection scenario, and is set to the number of the slot where the
parent-node UCIU locates in UCIU-UMPT interconnection scenario.
○ CTPLLNK Parent Node Port No.: This parameter is fixedly set to 8 in
UMPT interconnection scenario, and is set to a value within the range of
0 to 4 in UCIU-UMPT interconnection scenario.
NOTICE
If the parameter setting is inconsistent with the actual configuration, the OM
channel may be connected to an incorrect board, therefore failing to establish
the emergency OM channel.
Establishment Result Verification
After an emergency OM channel is successfully established, a message indicating the
successful establishment will be displayed on the Web LMT, as shown in Figure 3-8.
Figure 3-8 Message for successful emergency OM channel establishment
If the emergency OM channel fails to be established, a message indicating the establishment
failure will be displayed on the Web LMT, as shown in Figure 3-9.
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Figure 3-9 Message for emergency OM channel establishment failure
If the establishment fails, check and handle faults according to the following causes:
l The connection of the remote OM channel or local LMT of the target base station is
normal. If the OM channel between the target base station and the U2000 is normal or
the target base station is locally logged in to using the Web LMT, the emergency OM
channel cannot be established.
NOTICE
An emergency OM channel is an emergent troubleshooting method for fault scenarios.
Its priority is lower than that of normal maintenance methods. In normal maintenance
modes, do not establish emergency OM channels.
l An emergency OM channel has been established on the target or proxy base station.
During the establishment of an emergency OM channel, a single main control board can
serve as or is served by the proxy of only one main control board within the MBTS.
l The emergency OM channel is immediately enabled after they automatically disable due
to exceptions on the target or proxy base station. For example, the target or proxy base
station resets, or the transmission on the emergency OM channel is interrupted for a
period and then recovers. If an emergency OM channel disables abnormally, it retains
between the target and proxy base stations within five minutes after the disabling and
deletes automatically after five minutes.
l The target base station does not support the establishment of the emergency OM channel.
Emergency OM channel is unavailable if the GBTS serves as the target base station.
l The number of emergency OM channels established on a GBSC exceeds the maximum
value. Currently, a maximum of 30 emergency OM channels can be established on the
GBTSs connecting to one GBSC. If the number exceeds the maximum value, a message
indicating establishment failure will be displayed. In this case, existing emergency OM
channels can be disabled so that a new emergency OM channel can be established.
l Emergency OM channel establishment expires. Establishment expiration may be caused
by location information configuration failure of the target base station, the main control
board of the target base station being the standby board, or internal communication
errors. The handling suggestions are as follows:
a. Ensure that the location information of the target base station is correctly
configured.
b. Ensure that the main control board of the target base station works in the active
mode.
c. Check whether the OM link is congested if the GBTS serves as the proxy base
station. If yes, establish the emergency OM channel when the OM link is not
congested.
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l If the fault persists, contact Contacting Huawei Technical Support.
3.5.4 Function Description
This chapter describes the function description of Proxy PNP Trace.
Proxy PNP Trace
After the emergency channel is enabled, you can use the Proxy PNP Trace function on the
proxy base station to start a PNP tracing task for the target base station so that remote
monitoring can be performed for the PnP deployment of the target base station.
NOTE
To start a proxy PNP tracing task on the GBSC LMT, information of the proxy base station must be
specified.
The proxy PNP tracing task provides the same functions as a common PNP tracing task. Both
can be started and stopped, and the tracing results can be automatically or manually saved.
NOTICE
PNP tracing applies only to the IP protocol stack.
Figure 3-10 and Figure 3-11 show the dialog box for setting parameters and the main
window for showing tracing results of a proxy PNP tracing task on the GBSC LMT,
respectively.
Figure 3-10 Dialog box for setting parameter on the GBSC LMT
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Figure 3-11 Main window for showing tracing results on the GBSC LMT
Figure 3-12 shows the main window for showing tracing results of a proxy PNP tracing task
on the LMT of eGBTS/NodeB/eNodeB (taking the eGBTS as an example below).
Figure 3-12 Main window for showing tracing results on the LMT of eGBTS/NodeB/eNodeB
Proxy MML
After the emergency OM channel is established, MML commands can be delivered to the
target base station. If the GBTS serves as the proxy base station, choose BTS Maintenance >
MML By Proxy on the GBSC LMT, and then input the commands.
l Figure 3-13 shows the main window for using the Proxy MML function on the GBSC
LMT.
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Figure 3-13 Main window for using Proxy MML on the GBSC LMT
The details about the Proxy MML function on the GBSC LMT are as follows:
– Commands can only be manually input or copied to the MML command input area.
– Batch execution of MML commands is supported. The user can input a maximum
of 20 commands at a time and the LMT executes the commands one by one.
– Commands can be entered, copied, pasted, and deleted.
– Command outputs can be manually or automatically saved and can be cleared.
– Format check can be performed for commands. However, semantic check and
parameter check are not supported.
– The command expiration complies with the expiration mechanism set for all
commands on the LMT.
– CTRL+Q can be pressed to stop ping commands.
l Figure 3-14 shows the main window for using the Proxy MML function on the LMT of
eGBTS/NodeB/eNodeB (taking the eGBTS as an example below).
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Figure 3-14 Main window for using Proxy MML on the LMT of eGBTS/NodeB/
eNodeB
The details about the Proxy MML function on the LMT of eGBTS/NodeB/eNodeB are
as follows:
– To deliver commands to the target base station, select the Use MML By Proxy
check box. To execute commands on the proxy base station, clear the Use MML By
Proxy check box.
– Both the command outputs for the proxy and target base stations will be printed in
the Common Maintenance tab page.
– Command auto-displaying, parameter check, and semantic check are supported for
commands of the target base station based on the Macro.ini of the proxy base
station. The navigation tree, search, operation record, online help, historical
command help, and execution function are the same as those of normal MML.
– Performing the preceding checks based on the Macro.ini of the proxy base station
may result in mismatch in MML command sets, parameters, and descriptions with
those of the target base station. The differences are as follows:
n RAT-related command sets: RAT-related commands cannot be delivered using
the emergency OM channel.
n Common command sets: ATM-related commands are not supported on
GBTSs/eGBTSs and eNodeBs and IPv6-related commands are not supported
on GBTSs and NodeBs. If a GBTS/eGBTS or an eNodeB serves as the proxy
of a NodeB, ATM-related commands cannot be input. If a NodeB serves as the
proxy of a GBTS/eGBTS or an eNodeB, ATM-related commands can be input
but cannot be executed on the GBTS/eGBTS or eNodeB.
n Online help and attribute information in notes: Only the online help and
attribute information in notes of the proxy base station can displayed.
– When the Use MML By Proxy check box is selected, only format check rather than
semantic check can be performed for the commands entered or copied in the MML
command input area. The commands are directly delivered to the target base
station. These commands cannot be displayed in the Command History text box,
which ensure that the commands having differences in two RATs can be normally
input.
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– CTRL+Q can be pressed to stop ping commands.
3.5.5 Troubleshooting
This chapter provides methods of troubleshooting Proxy status and MML command execution
exceptions.
Abnormal Proxy Status
During the enabling or operation of proxy functions, the functions may automatically disable.
The causes are as follows:
l The connection of the remote OM channel or local LMT of the target base station
restores.
l The communication among the Web LMT, proxy base station, and target base station is
abnormal, or the proxy base station is busy.
For the first cause, the Web LMT displays a message and the target base station automatically
switches to the normal OM channel for maintenance.
For the second cause, whether the connection between the Web LMT and the proxy base
station is normal must be checked first. If the connection is abnormal, restore the connection.
If the connection is normal and the GBTS serves as the proxy base station, check whether the
OM link is congested using an Abis interface tracing task.
NOTE
If the connection is normal and the eGBTS/NodeB/eNodeB serves as the proxy base station, the
bandwidth is large and OM link congestion seldom occurs. In this case, no message tracing is required
for checking the congestion.
MML Command Execution Exception
l When the GBTS serves as the proxy base station, commands for querying logs, such as
alarm logs and operation logs, generates a large number of messages to be reported. In
this case, the commands may be discarded by the GBTS due to capability limitation.
Therefore, it is not recommended such commands be executed on the emergency OM
channel, especially when GTMUa is used as the main control board of the GBTS as its
data processing capability is limited. n the preceding case, the command execution
expiration is displayed.
l Commands related to FTP file transfer fail to be executed due to the following reason:
File transfer is based on FTP and the FTP server is on the LMT. An emergency OM
channel only enables commands related to FTP file transfer to be delivered to the target
base station and to be executed. However, the FTP server is unreachable, and therefore
file transfer fails. If the multimode base station properly connects to the FTP server,
commands related to FTP file transfer can be executed.
3.5.6 Example of Using the Proxy MML Function
The emergency OM channel does not support the transmission of configuration file using an
FTP server. Therefore, the OM channel must be established for the target base station as soon
as possible using MML commands. This section describes how to establish an OM channel
for the target base station using the Proxy MML function in separate transmission networking
with an SeGW, separate transmission networking without an SeGW, and co-transmission
networkingseparate transmission networking without an SeGW and co-transmission
networking.
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Separate Transmission Networking with an SeGW
Figure 3-15 shows the separate transmission networking with an SeGW.
Figure 3-15 Separate transmission networking with an SeGW
Assume that the OM channel of the eNodeB is faulty and the GBTS/eGBTS serves as the
proxy base station. Establish the emergency OM channel for the eNodeB as follows:
1. Configure the OM channel.
a. Disable f the DHCP detection. The following is a command example:
SET DHCPSW: SWITCH=DISABLE;
b. Add a cabinet. The following is a command example:
ADD CABINET: CN=0, TYPE=APM30;
c. Add a subrack. The following is a command example:
ADD SUBRACK: CN=0, SRN=0, TYPE=BBU3900;
d. Add a board. The following is a command example:
ADD BRD: CN=0, SRN=0, SN=7, BT=UMPT:;
e. Add an Ethernet port. The following is a command example:
ADD ETHPORT: CN=0, SRN=0, SN=7, SBT=BASE_BOARD, PN=0, PA=COPPER,
MTU=1500, SPEED=100M, DUPLEX=FULL, FC=OPEN:;
f. Add the interface IP address for the OM channel. The following is a command
example:
ADD DEVIP: CN=0, SRN=0, SN=7, SBT=BASE_BOARD, PT=ETH, PN=0,
IP="192.168.20.188", MASK="255.255.255.0":;
g. Add the route for the OM channel. The following is a command example:
ADD IPRT: RTIDX=0, CN=0, SRN=0, SN=7, SBT=BASE_BOARD,
DSTIP="192.168.60.60", DSTMASK="255.255.255.0", RTTYPE=NEXTHOP,
NEXTHOP="192.168.20.1";
NEXTHOP="192.168.20.1";
h. Add an OM channel. The following is a command example:
ADD OMCH: FLAG=MASTER, IP="192.168.31.188", MASK="255.255.255.0",
PEERIP="192.168.60.60", PEERMASK="255.255.255.0", BEAR=IPV4, BRT=YES,
RTIDX=0, BINDSECONDARYRT=NO, CHECKTYPE=NONE:;
2. Configure the IPSec tunnel.
a. Configure the local IKE. The following is a command example:
SET IKECFG: IKELNM="IKECFG1", IKEKLI=20, IKEKLT=60, DSCP=48;
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b. Add the IKE proposal. The following is a command example:
ADD IKEPROPOSAL: PROPID=10, ENCALG=3DES, AUTHALG=MD5,
AUTHMETH=IKE_RSA_SIG, DHGRP=DH_GROUP14, DURATION=86400;
c. Add the IKE peer. The following is a command example:
ADD IKEPEER: PEERNAME="ike", PROPID=10, IKEVERSION=IKE_V1,
EXCHMODE=MAIN, IDTYPE=IP, REMOTEIP="192.168.90.90", REMOTENAME="secgw",
DPD=PERIODIC, DPDIDLETIME=20, DPDRETRI=4, DPDRETRN=6,
LOCALIP="192.168.20.188";
d. Add an ACL. The following is a command example:
ADD ACL: ACLID=3000, ACLDESC="for IPsec";
e. Add ACL rules to the ACL. The following is a command example:
ADD ACLRULE: ACLID=3000, RULEID=1, ACTION=PERMIT, PT=IP,
SIP="192.168.31.188", SWC="0.0.0.0", DIP="192.168.60.60", DWC="0.0.0.0",
MDSCP=NO;
f. Add the IPSec proposal. The following is a command example:
ADD IPSECPROPOSAL: PROPNAME="prop0", ENCAPMODE=TUNNEL, TRANMODE=ESP,
ESPAUTHALG=MD5,ESPENCALG=DES;
g. Add the IPSec security policy. The following is a command example:
ADD IPSECPOLICY: SPGN="Policy", SPSN=1, ACLID=3000, PROPNAME="prop0",
PEERNAME="ike", PFS= DISABLE, LTCFG=LOCAL, LTS=86400,
REPLAYWND=WND_DISABLE;
h. Bind the IPSec security policy and the outgoing port. The following is a command
example:
ADD IPSECBIND: CN=0, SRN=0, SN=7, SBT=BASE_BOARD, PT=ETH, PN=0,
SPGN="Policy";
3. If the base station has obtained the device certificate of the operator, perform the
following operation to enable it to take effect.
a. Set the parameters related to the application certificate. The following is a
command example:
MOD APPCERT: APPTYPE=IKE, APPCERT="OPKIDevCert.cer ";
The base station automatically obtains the device certificate from the CA during
PnP deployment or shares the device certificate with the main control board of
another board.
4. If the base station has not obtained the device certificate of the operator, manually obtain
the certificate. The PKI process is as follows:
a. Specify the main control board for loading the device certificate on the eNodeB.
The following is a command example:
SET CERTDEPLOY: DEPLOYTYPE=SPECIFIC, CN=0, SRN=0, SN=7;
b. Set the parameters related to certificate request template. The following is a
command example:
MOD CERTREQ: COMMNAME=ESN, USERADDINFO=".huawei.com", COUNTRY="CN",
ORG="ITEF", ORGUNIT="Hw", STATEPROVINCENAME="sc", LOCALITY="cd",
KEYUSAGE=DATA_ENCIPHERMENT-1&DIGITAL_SIGNATURE-1&KEY_AGREEMENT-1&KEY_ENCI
PHERMENT-1, SIGNALG=SHA1, KEYSIZE=KEYSIZE1024,
LOCALNAME="abcdefghijklmn.huawei.com", LOCALIP="192.168.20.188";
c. Set the parameters related to the CA server of the operator. The following is a
command example:
ADD CA: CANAME="C = AU, S = Some-State, O = Internet Widgits Pty Ltd, CN
= eca1", URL="http://88.88.88.88:80/pkix/";
d. Set the parameters required for device certificate application for the eNodeB. The
following is a command example:
REQ DEVCERT: CANAME="C=AU, S=Some-State, O=Internet Widgits Pty Ltd,
CN=eca1", APPCERT="OPKIDevCert.cer";
After the configuration takes effect, the certificate application starts.
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e. Load the root certificate of the operator. The following is a command example:
ADD TRUSTCERT: CERTNAME="OperationCA.cer";
f. Set the parameters related to the application certificate. The following is a
command example:
MOD APPCERT: APPTYPE=IKE, APPCERT="OPKIDevCert.cer ";
g. Set the tasks for periodically checking the certificate validity. The following is a
command example:
SET CERTCHKTSK: ISENABLE=ENABLE, PERIOD=7, ALMRNG=30, UPDATEMETHOD=CMP;
h. Download the CRL file. The following is a command example:
DLD
CERTFILE:IP="192.168.60.60",USR="admin",PWD="*****",SRCF="eNodeB.crl",DST
F="eNodeB.crl";
i. (Optional) Set the parameters related to CRL. The following is a command
example:
ADD CRL: CERTNAME="eNodeB.crl";
j. (Optional) Set the parameters related to periodical CRL download task. The
ADD CRLTSK: IP="192.168.86.86", USR="admin", PWD="*****",
FILENAME="NodeB.crl", ISCRLTIME=DISABLE, TSKID=0, CRLGETMETHOD=FTP;
k. (Optional) Set the CRL application policy. The following is a command example:
SET CRLPOLICY: CRLPOLICY= NOVERIFY;
5. Observe the OM Channel State and check whether the OM channel state is normal. The
DSP OMCH: FLAG=MASTER;
6. Observe the IPSec Tunnel.
a. Check the status of the IKE SA. Run the following command and check whether the
SA FLAG is Ready in the command output:
DSP IKESA: CN=0, SRN=0, SN=7, IKEVSN=IKE_V1, DSPMODE=VERBOSE,
IKEPNM="peer", PHASE=PHASE1;
If yes, go to step 6.b. If no, IPSec fails to be activated.
b. Check the status of the IPSec SA. Run the following command and check whether
IPSec SA data is displayed in the command output:
DSP IPSECSA: CN=0, SRN=0, SN=7, SPGN="policy", SPSN=1;
If yes, this feature has been activated.
c. Check whether services are properly protected by the IPSec tunnel. Run the
following command to check the ACL rules and determine whether services are
properly protected by the IPSec tunnel:
LST ACLRULE:;
7. Observe PKI features.
a. Check the status of the device certificate. Run the following command and check
whether the certificate loading state is normal in the command output:
DSP APPCERT:;
If yes, the device certificate has been loaded on the eNodeB.
b. Check the status of the trust certificate. Run the following command and check
whether the certificate loading state is normal in the command output:
DSP TRUSTCERT:;
If yes, the trust certificate has been loaded on the eNodeB.
c. (Optional) Check the CRL status. Run the following command and check whether
the certificate loading state is normal in the command output:
DSP CRL:;
If yes, the CRL has been loaded on the eNodeB.
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Separate Transmission Networking Without an SeGW
Figure 3-16 shows the separate transmission networking without an SeGW.
Figure 3-16 Separate transmission networking without an SeGW
Establish the emergency OM channel for the eNodeB as follows:
a. Turn off the DHCP detection. The following is a command example:
e. Add an Ethernet port. The following is a command example:
ADD ETHPORT: CN=0, SRN=0, SN=7, SBT=BASE_BOARD, PN=0, PA=COPPER,
MTU=1500, SPEED=100M, DUPLEX=FULL, FC=OPEN:;
f. Add the interface IP address for the OM channel. The following is a command
example:
ADD DEVIP: CN=0, SRN=0, SN=7, SBT=BASE_BOARD, PT=ETH, PN=0,
IP="192.168.20.188", MASK="255.255.255.0":;
g. Add the route for the OM channel. The following is a command example:
NEXTHOP="192.168.20.1";
NEXTHOP="192.168.20.1";
h. Add an OM channel. The following is a command example:
2. Observe the OM channel state and check whether the OM channel state is normal. The
Co-Transmission Networking
Figure 3-17 shows the co-transmission networking.
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29

Figure 3-17 Co-transmission networking
Establish the emergency OM channel for the eNodeB as follows:
a. Turn off the DHCP detection. The following is a command example:
e. Add the route for the OM channel. The following is a command example:
ADD IPRT: RTIDX=0, CN=0, SRN=0, SN=6, SBT=BACK_BOARD,
DSTIP="192.168.60.60", DSTMASK="255.255.255.0", RTTYPE=IF, IFT=TUNNEL;
f. Add an OM channel. The following is a command example:
2. Check whether the OM channel state is normal. The following is a command example:
If no, the OM channel is faulty.
3.5.7 Other Operations
This chapter describes the other operations of MBTS emergency OM channel.
Query the MAC Address of the Target Base Station
To obtain the MAC address of the target base station, run the following command:
DSP ETHPORT: CN=0, SRN=0, SN=7, SBT=BASE_BOARD;
Query the ESN of the Main Control Board in the Target Base Station
To obtain the ESN of the main control board, run the following command:
LST ESN:;
3.6 Remote Query of Services on Disconnected eNodeBs
This section describes the function, application scenarios, and methods of remotely querying
services on disconnected eNodeBs based on X2 interface tracing.
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3.6.1 Overview
Function Introduction
This function supports the query of resources and services on neighboring eNodeBs based on
X2 interface tracing when neighboring eNodeBs are disconnected from the OSS.
Figure 3-18 Remote query of services on disconnected eNodeBs
3.6.2 Application Scenarios
When an eNodeB is disconnected from the OSS, services on the eNodeB must be timely
queried to check whether the services are interrupted. Whether the fault is reported is based
on the query results, and accordingly the fault level is determined.
3.6.3 Function Description
1. Query the X2 interface state of the disconnected peer eNodeB.
Run the DSP X2INTERFACE command.
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Figure 3-19 Checking command outputs
NOTE
l If the X2 interface is normal, go to the next step.
l If the X2 interface is abnormal, the disconnected peer eNodeB may experience transmission
failures, and the eNodeB operating state cannot be queried based on X2 interface tracing.
2. Start an X2 interface tracing task.
a. Create an X2 interface tracing task by choosing Monitor > Signaling Trace >
Signaling Trace Management > LTE > Application Layer > X2 Interface Trace.
b. Specify the ID of the peer eNodeB to be traced, as shown in Figure 3-20.
Figure 3-20 Specifying the ID of the peer eNodeB to be traced
c. Click Finish to start the X2 interface tracing task.
3. Run an MML command to report services on the neighboring eNodeB.
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Run the CHK NBRENODEB: NbrENodeBId=xx, Mcc="xx", Mnc="xx" command, as
shown in Figure 3-21.
Figure 3-21 Running the CHK NBRENODEB command
NOTE
This command is used to query response messages from neighboring eNodeBs, which facilitates service
query on neighboring eNodeBs.
4. Query services on the neighboring eNodeB.
a. In X2 interface tracing results, query the RESOURCE STATUS UPDATE message
sent from the disconnected peer eNodeB, as shown in Figure 3-22.
Figure 3-22 Querying the RESOURCE STATUS UPDATE message
b. Among the messages traced over the X2 interface, the local eNodeB sends the peer
eNodeB a RESOURCE STATUS REQUEST message, instructing the peer eNodeB
to report service status, as shown in Figure 3-23.
Figure 3-23 Instructing the peer eNodeB to report service status
c. Check service status on the peer eNodeB sending the RESOURCE STATUS
UPDATE message, as shown in Figure 3-24.
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Figure 3-24 Checking service status on the peer eNodeB
d. After receiving the first RESOURCE STATUS UPDATE message sent from the
peer eNodeB, the local eNodeB sends the peer eNodeB another RESOURCE
STATUS REQUEST message, instructing the peer eNodeB to stop reporting service
status, as shown in Figure 3-25.
Figure 3-25 Instructing the peer eNodeB to stop reporting service status
3.6.4 Troubleshooting
If no messages sent from the disconnected peer eNodeB can be found in the X2 interface
tracing results, repeatedly execute the CHK NBRENODEB command and then check whether
messages sent from the peer eNodeB are received.
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4Troubleshooting Access Faults
About This Chapter
This chapter describes how to diagnose and handle access faults.
4.1 Definitions of Access Faults
If an access fault occurs, UEs have difficulty accessing the network due to radio resource
control (RRC) connection setup failures or E-UTRAN radio access bearer (E-RAB) setup
failures.
4.2 Background Information
This section provides counters and alarms related to access faults, and methods for analyzing
topN cells.
4.3 Troubleshooting Method
This section describes how to identify and troubleshoot the possible cause.
4.4 Troubleshooting Access Faults Caused by Incorrect Parameter Configurations
This section provides information required to troubleshoot access faults due to incorrect
parameter configurations. The information includes fault descriptions, background
information, possible causes, fault handling method and procedure, and typical cases.
4.5 Troubleshooting Access Faults Caused by Radio Environment Abnormalities
This section provides information required to troubleshoot access faults due to radio
environment abnormalities. The information includes fault descriptions, background
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eRAN Troubleshooting Guide 4 Troubleshooting Access Faults
35

4.1 Definitions of Access Faults
If an access fault occurs, UEs have difficulty accessing the network due to radio resource
control (RRC) connection setup failures or E-UTRAN radio access bearer (E-RAB) setup
failures.
4.2 Background Information
This section provides counters and alarms related to access faults, and methods for analyzing
topN cells.
In Long Term Evolution (LTE) networks, access faults occur either during radio resource
control (RRC) connection setup or during E-UTRAN radio access bearer (E-RAB) setup. The
access success rate is a key performance indicator (KPI) that quantifies end user experience.
An excessively low access success rate indicates that end users have difficulty making
mobile-originated or mobile-terminated calls.
Related Counters
l Measurement related to RRC setup (RRC.Setup.Cell)
l Measurement related to RRC setup failure (RRC.SetupFail.Cell)
l Measurement related to E-RAB establish (E-RAB.Est.Cell)
l Measurement related to E-RAB establish failure (E-RAB.EstFail.Cell)
For 3900 series base stations, see eNodeB Performance Counter Reference. For the
BTS3202E, see BTS3202E Performance Counter Reference. For the BTS3911E, see
BTS3911E Performance Counter Reference
Related Alarms
l Hardware-related alarms
– ALM-26104 Board Temperature Unacceptable
– ALM-26106 Board Clock Input Unavailable (Applicable to 3900 series base
stations only)
– ALM-26107 Board Input Voltage Out of Range (Applicable to 3900 series base
stations only)
– ALM-26200 Board Hardware Fault
– ALM-26202 Board Overload
– ALM-26203 Board Software Program Error
– ALM-26208 Board File System Damaged
l Temperature-related alarms (Applicable to 3900 series base stations only)
– ALM-25650 Ambient Temperature Unacceptable
– ALM-25651 Ambient Humidity Unacceptable
– ALM-25652 Cabinet Temperature Unacceptable
– ALM-25653 Cabinet Humidity Unacceptable
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– ALM-25655 Cabinet Air Outlet Temperature Unacceptable
– ALM-25656 Cabinet Air Inlet Temperature Unacceptable
l Link-related alarms
– ALM-25880 Ethernet Link Fault
– ALM-25886 IP Path Fault
– ALM-25888 SCTP Link Fault
– ALM-25889 SCTP Link Congestion
– ALM-26233 BBU CPRI Optical Interface Performance Degraded (Applicable to
3900 series base stations only)
– ALM-26234 BBU CPRI Interface Error (Applicable to 3900 series base stations
only)
– ALM-29201 S1 Interface Fault
– ALM-29207 eNodeB Control Plane Transmission Interruption
– ALM-25904 IP Link Performance Measurement Fault
l RF-related alarms
– ALM-26239 RX Channel RTWP/RSSI Unbalanced Between RF Units (Applicable
to 3900 series base stations only)
– ALM-26520 RF Unit TX Channel Gain Out of Range
– ALM-26521 RF Unit RX Channel RTWP/RSSI Too Low
– ALM-26522 RF Unit RX Channel RTWP/RSSI Unbalanced
– ALM-26527 RF Unit Input Power Out of Range
– ALM-26534 RF Unit Overload
– ALM-26562 RF Unit and RET Antenna Connection Failure (Applicable to 3900
series base stations only)
– ALM-26524 RF Unit PA Overcurrent
– ALM-29248 RF Out of Service
l Configuration-related alarms
– ALM-26245 Configuration Data Inconsistency
– ALM-26812 System Dynamic Traffic Exceeding Licensed Limit
– ALM-26815 Licensed Feature Entering Keep-Alive Period
– ALM-26818 No License Running in System
– ALM-26819 Data Configuration Exceeding Licensed Limit
– ALM-29243 Cell Capability Degraded
– ALM-29247 Cell PCI Conflict
l Cell-related alarms
– ALM-29240 Cell Unavailable
– ALM-29241 Cell Reconfiguration Failed
– ALM-29245 Cell Blocked
TopN Cell Selection
TopN cells can be selected by analyzing the daily KPI file exported by the U2000.
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l Top3 cells with the largest amounts of failed RRC connection setups
(L.RRC.ConnReq.Att - L.RRC.ConnReq.Succ) and lowest RRC connection setup
success rates
l Top3 cells with the largest amounts of failed E-RAB setups and lowest E-RAB setup
success rates
Tracing TopN Cells
After finding out topN cells and the periods when they have the lowest success rates, start Uu,
S1, and X2 interface tracing tasks and check the exact point where the RRC connection or E-
RAB setup fails.
In addition, after the Evolved Packet Core (EPC) obtains the international mobile subscriber
identity (IMSI) of the UE with the lowest success rate based on the UE's temporary mobile
subscriber identity (TMSI), you can start a task to trace the UE throughout the whole network.
Analyzing Environmental Interference to TopN Cells
Environmental interference to a cell consists of downlink (DL) interference and uplink (UL)
interference to the cell. The following methods can be used to check the environmental
interference:
l To check DL interference, use a spectral scanner. If both neighboring cells and external
systems may cause DL interference to the cell, locate the exact source of the DL
interference.
l To check UL interference, start a cell interference detection task and analyze the result.
4.3 Troubleshooting Method
This section describes how to identify and troubleshoot the possible cause.
Possible Causes
Scenario Fault Description Possible Causes
The RRC connection fails to
be set up.
l The UE cannot search
cells.
l A fault occurs in radio
interface processing.
l Top user problems occur.
l Parameters of the UE or
eNodeB are incorrectly
configured.
l The radio environment is
abnormal.
l The UE is abnormal.
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Scenario Fault Description Possible Causes
The E-RAB fails to be set
up.
l Resources are
insufficient.
l A fault occurs in radio
interface processing.
l The EPC is abnormal.
l Top user problems occur.
l Parameters of the UE or
eNodeB are incorrectly
configured.
l The radio environment is
abnormal.
l Parameters of the
Evolved Packet Core
(EPC) are incorrectly
configured.
l The UE is abnormal.
Troubleshooting Flowchart
Figure 4-1 shows the troubleshooting flowchart for handling low RRC connection setup rate
and low E-RAB setup rate.
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39

Figure 4-1 Troubleshooting flowchart for handling low RRC connection setup rate and low
E-RAB setup rate
Troubleshooting Procedure
1. Select topN cells.
2. Check whether parameters of the UE or eNodeB are incorrectly configured.
– Yes: Correct the parameter configurations. Go to 3.
– No: Go to 4.
3. Check whether the fault is rectified.
– Yes: End.
– No: Go to 4.
4. Check whether the radio environment is abnormal.
– Yes: Handle abnormalities in the radio environment. Go to 5.
– No: Go to 6.
eRAN11.1
40

– Yes: End.
– No: Go to 6.
6. Check whether parameters of the EPC are incorrectly configured.
– Yes: Correct the parameter configurations. Go to 7.
– No: Go to 8.
– Yes: End.
– No: Go to 8.
8. Contact Huawei technical support.
4.4 Troubleshooting Access Faults Caused by Incorrect
Parameter Configurations
This section provides information required to troubleshoot access faults due to incorrect
parameter configurations. The information includes fault descriptions, background
Fault Description
l The UE cannot receive broadcast information from the cell.
l The UE cannot receive signals from the cell.
l The UE cannot camp on the cell.
l The end user complains about an access failure, and the value of the performance
counter L.RRC.ConnReq.Att is 0.
l An RRC connection is successfully set up for the UE according to standard interface
tracing results, but then the mobility management entity (MME) releases the UE because
the authentication procedure fails.
l The end user complains that the UE can receive signals from the cell but is unable to
access the cell.
l According to the values of the performance counters on the eNodeB side, the number of
RRC connections that are successfully set up is much greater than the number of E-
RABs that are successfully set up.
l According to the KPIs, the E-RAB setup success rate is relatively low, and among all
cause values, the cause values indicated by L.E-RAB.FailEst.TNL and L.E-
RAB.FailEst.RNL contribute a large proportion.
Related Information
None
Possible Causes
l Cell parameters are incorrectly configured. For example, the E-UTRA absolute radio
frequency number (EARFCN), public land mobile network (PLMN) ID, threshold used
in the evaluation of cell camping, pilot strength, and access class.
l The UE has special requirements for authentication and encryption.
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41

l Parameters of the subscriber identity module (SIM) card or registration-related
parameters on the home subscriber server (HSS) are incorrectly configured.
l The authentication and encryption algorithms are incorrectly configured on the Evolved
Packet Core (EPC).
l The IPPATH or IPRT managed objects (MOs) are incorrectly configured.
Troubleshooting Flowchart
Figure 4-2 Troubleshooting flowchart for access faults due to incorrect parameter
configurations
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Troubleshooting Procedure
1. Check whether cell parameters are incorrectly configured. Pay special attention to the
following parameter settings as they are often incorrectly configured: the EARFCN,
PLMN ID, threshold used in the evaluation of cell camping, pilot strength, and access
class.
Yes: Correct the cell parameter configurations. Go to 2.
No: Go to 3.
Yes: End.
No: Go to 3.
3. Check the type and version of the UE and determine whether the authentication and
encryption functions are required.
Yes: Enable the authentication and encryption functions. Go to 4.
No: Go to 5.
Yes: End.
No: Go to 5.
5. Check whether parameters of the SIM card or registration-related parameters on the HSS
are incorrectly configured. The parameters of the SIM card include the K value,
originating point code (OPC), international mobile subscriber identity (IMSI), and
whether this SIM card is a UMTS SIM (USIM) card.
Yes: Correct the parameter configurations. Go to 6.
No: Go to 7.
Yes: End.
No: Go to 7.
7. Check whether the authentication and encryption algorithms are incorrectly configured
on the EPC. For example, check whether the switches for the algorithms are turned off.
Yes: Modify the parameter configuration on the EPC. Go to 8.
No: Go to 9.
Yes: End.
No: Go to 9.
9. Check whether the IPPATH or IPRT MOs are incorrectly configured.
Yes: Correct the MO configurations. Go to 10.
No: Go to 11.
Yes: End.
No: Go to 11.
11. Check whether the fault can be diagnosed by tracing the access signaling procedure.
Yes: Handle the fault. Go to 12.
No: Go to 13.
eRAN11.1
43

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