Training Document_LTE Hardware Operation and Maintenance-20130630-A-1.0

www.huawei.com

Security Level: Internal Use

HUAWEI TECHNOLOGIES Co., Ltd. HUAWEI Confidential

LTE Hardware Operation and Maintenance

HUAWEI TECHNOLOGIES CO., LTD. HUAWEI Confidential

Chapter 1 BBU Architecture

Chapter 2 Hardware Fault Alarms

Chapter 3 Indicator Functions


BBU Architecture – Logical Relationships Between Different Systems

控及时钟模块

Back plane

BBI

MPT

BBP RFU

TRP

LMILMT

RRU

Control plane

INUSCU

CLKIHigh-speed user

CIU/EXU

CLKI

PWRFAN

BBU interconnection

Controller

BBP

BBIs and BBPs run on the same type of board and the availability of CPRI ports on these boards depends on their slot numbers.

An MPT board provides clock, transmission, and operation and maintenance functions.


FAN

SLOT0(BBP, TRP, SCU, and CIU) SLOT4(BBP, TRP, SCU, and CIU)

POWER0

SLOT1 (BBP, BBI, TRP, SCU, and CIU) SLOT5(BBP, TRP, SCU, and CIU)

SLOT2(BBP, BBI, TRP, SCU, and CIU) SLOT6(MPT, EXU, SCU, and TRP)

POWER1

SLOT3(BBP, BBI, TRP, SCU, and CIU) SLOT6(MPT, EXU, SCU, and TRP)

BBU Architecture – Slots of Main Control and Baseband Boards

In most cases, MPTs are inserted

in slots 6 and 7 and work in

active/standby mode. In dual-

mode scenario, they can be

configured to work in active/active

mode.

The system has eight board slots, two power supply slots, and a fan slot.


BBU Architecture - LBBPc Board Structure

Module Function

CPU small system module

Key service channel and control center

Baseband processing module

Consists of the FPGA and DSP. The DSP performs uplink service processing based on algorithms.The FPGA performs uplink and downlink baseband processing, encrypts data, and performs CPRI framing.

Control logic module

Watchdog, resetFPGA loadingIOBUS transparent data transmission

CAN moduleMonitors and manages boards

Clock moduleManages the clock resources of boards

Power supply module

Controls the sequence for supplying boards with power and for powering on the boards

RapidIO Switch module

Responsible for data exchanges between chips

JTAG module Debugs and loads software

CPU

DDR2 DDR2DDR2 DDR2 DDR2 DDR2 DDR2 DDR2

SFPGE

FLASH CPLD

RS

T

GP

IOSGMII 1

SGMII 2

SGMII4

IDX1IN

T

IO BUS

JTAG

DDR2

UART

FPGA0

BSBGPIO

SG

MII

0

IO BUS

FPGA1

CLK

POWER

DSP 0

DSP 1

DSP 2SGMII 7

SGMII 6

SGMII 5

66 . 67 M CORE

125 M SGMII

125 M SRIO

V33V25V18VA10

V09 COREV09 VTT

RIOSW

UA

RT

RIO1*1X

232

PHY

SG

MII

3


BBU Architecture – LBBPd Architecture

pan

el

CPU

bac

kbo

ard

ASIC A

FPGA

RIOSW

ASIC B

LCPRI*3 3.072G

MPT—> CPU IDX1

HDLC

SGMII*1

LBUS*2 4.9152G

uart, rsv_io

DBUS 8bit*122.88M

1

2

2

3

4

2

maintenance: GE*1

CPU_SRIO 3.125*4

SRIO*4 operation

reserve HDLC

CPRI extend

SGMII*2 encrypt

SRIO*1 load &maintenance

CPRI*6


BBU Architecture – Main Control Boards Working in Active/Standby Mode

SWITCH (active)6#

SWITCH (standby)7#

BBI/BB/TRP0#

BB/TRP2#

BB/TRP3#

BB/TRP5#

BBI/BB/TRP

1#

BB/TRP4#

MPT CPU (active)

MPT CPU(standby)

GMII/RGMII GMII/RGMII

1 2 3 4 5 6

7

123456

7


BBU Architecture – Signal Transmission on the Main Control BoardTransmission directions of signals on front panels

The red lines indicate the transmission directions of signals at electrical ports.The green lines indicate the transmission directions of signals at optical ports.After the FPGA receives four input signals, it chooses two of them to send out to lower-level devices.


Hardware Fault Alarms

Troubleshooting guideline

1. Refer to the alarm online help to clear the alarm.

2. As an alternative, refer to the error locating guide to clear the alarm based on the

symptom. To view the error locating guide, visit http://support.huawei.com and choose

LTE TDD -> LTE TDD eNodeB -> Technical Guides -> Troubleshooting Guide.

3. Collect logs to assist in error locating. The commands for collecting one-click logging

files (brdlog) of each board are similar. The only difference lies in their cabinet,

subrack, and slot numbers.

A hardware error is difficult to locate without log and

serial port information, or even hardware test tools.

The customer or onsite engineers are required to be

capable of identifying a hardware error and then

replace the faulty board.


Hardware Alarm - 26205

Problem 1 ALM-26205 BBU Board Maintenance Link Failure

Symptom: The service channel between a baseband board and the main control board is disconnected and

there is a high probability that an alarm such as ALM 26200 Board Hardware Fault of ALM 26203 Board

Software Program Error is reported. If an alarm is reported, clear the alarm first.

Troubleshooting:

1. Power off the board that is reporting on the alarm. Then power on the board by running OPR BRDPWR.

Check whether the fault is rectified.

2. Reset the main control board by running RST BRD.

3. Remove the board that is reporting the alarm and check whether the pins on the connectors between the

board and the back plane are inserted properly. If they are inserted properly, insert the board to the

subrack again and check whether the fault is rectified.

4. Replace the baseband board.

5. Remove the main control board. Check whether the connectors between the main control board and the

back plane are inserted properly. If yes, insert the main control board and check whether the fault is

rectified.

6. Replace the main control board.

7. Replace the back plane.

Note: If the fault is not rectified after board replacement, the board is not faulty and do not treat it as a

damaged board.


Hardware Alarm - 26200/26234

Problem 2 ALM-26200 Board Hardware Fault

Root cause: The power supply, clock, or temperature of a board is abnormal.

Troubleshooting:

1. If the alarm is automatically cleared within 10 minutes and is no longer reported, the alarm is a false alarm

mistakenly reported during automatic software restoration. In this case, no hardware fault occurs and

troubleshooting is not required.

2. If the alarm persists for longer than 10 minutes, power off the board and then power on it. If you are at the site, pull

out the board and then insert it. If you are at the remote end, run OPR BRDPWR.

3. Check the indicators on the board panel at the site. If the RUN indicator is steady on, pull out the board and then

insert it to another slot. Check whether ALM-26200 is reported.

4. Replace the board.

Problem 3 Alarm ID: 26234 BBU CPRI Interface Error

Root cause: An error occurs when CPRI data is exchanged between the BBU and RRU over a CPRI link (link layer).

Troubleshooting:

1. Run DSP SFP to query the optical power of the optical module between the baseband board and the optical module.

Make sure that the optical power falls on the normal range.

2. Reset the RRU and the baseband board, and check whether the fault is rectified.

3. Use an optical power meter to check whether the optical module and optical fibers between the BBI and RRU are

working properly.

Note: To find the root cause in a timely manner, it is recommended that both qualified and faulty optical fibers be used

for cross testing.


Hardware Alarms - 26232/26201

Problem 4 ALM-26232 BBU Optical Module Transmit/Receive FaultSymptom: An error occurs when optical signals are exchanged between the BBU and RRU over an optical

link (physical layer).

Probable causes:

1. Optical fiber connectors on optical modules or optical modules of the baseband board are loosely

connected or the optical modules are faulty.

2. Optical fiber connectors on optical modules or optical modules of the RRU are loosely connected or the

optical modules are faulty.

3. Optical connectors on the ports used for the BBU to connect to lower-level radio frequency units are not

clean.

4. The working mode (single-mode or multi-mode) of optical modules is different from that of optical fibers.

5. The transmission rate of the optical modules on the baseband board is inconsistent with that on the RRU.

6. The optical connections between the BBU and the RRU are interrupted.

7. The RRU is faulty or is not powered on.

Perform troubleshooting by checking whether the problem is due to one of these causes.

Problem 5 ALM- 26201 Board Memory Soft FailureRoot cause: Part of data in the memory of the board is overwritten due to external electromagnetic

interference or radiation.

Troubleshooting:

1. Run RST BRDPWROFF to power off and then on the board.

2. Reset the main control board in slot 7.



Hardware Alarm - 26104

Problem 6: ALM-26104 Board Temperature Unacceptable

Root cause: The board temperature is out of the normal range.

Troubleshooting:

1. If only one board reports this alarm, run DSP BRDTEMP to check whether the temperature of

the board is higher than 85 . In addition, check whether temperatures of the boards in other ℃

slots fall on the normal range.

2. If the temperatures of all these boards are normal, the temperature sensor of the board

reporting this alarm may be faulty. In this case, the alarm is a false alarm mistakenly reported

by the board. Replace the board or ignore this alarm.

3. Check the temperature of each board in the BBU subrack. If the temperatures of all these

boards are higher than 85 , check whether a fan fault alarm is reported.℃

4. Check whether the BBU subrack is positioned in a high-temperature environment. If yes,

place it in a position where ventilation is good.

5. Check whether the air vent on each side of the BBU is blocked.

6. Check whether the three fans in the fan frame have stopped rotating.


Hardware Alarms - 26216/26204

Problem 7 ALM-26216 Board Not Securely Installed

Root cause: The pins between the board and the back plane are not inserted properly.

Troubleshooting:

1. Remove the board and then insert it again. Check whether the fault is rectified.

2. Remove the board and check whether any pin on the back plane is bent, fallen, or damaged. If any pin is

bent, fallen, or damaged, replace it.

3. Insert the board into another slot. Check whether ALM-26216 is reported. If yes, replace the board.

Problem 8 ALM-26204 Board Not In Position

Cause: The main control board detects that a board is not in position.

Troubleshooting:

1. Check whether the connectors between the board and the back plane are inserted properly.

2. Insert the board again and make sure that the board is properly connected to the back plane through

connectors.

3. Insert the board into another slot and check whether ALM-26204 is reported.


5. Remove and then insert the main control board that is in the same subrack as the faulty board.

6. Replace the main control board that is in the same subrack as the faulty board.


Indicator Functions

Label Color Blinking Frequency Meaning Remarks

RUN Green Steady on The power supply is normal but the board is faulty.

After the system is powered on, the RUN indicator is steady on. If the secure version is in use, the RUN indicator blinks at the frequency of 4 Hz. If the board starts properly, the RUN indicator blinks at the frequency of 0.5 Hz.　

　　 Steady off The board has no input power or is faulty.

　　 At the frequency of 0.5 Hz (on for 1 second and off for 1 second)

The board is running properly.

　　 4 HzThe board is loading software or being configured, is not started, or is running in a secure version.

ALM Red Steady on An alarm is reported and the board needs to be replaced.

The system can be configured to or not to turn on this indicator when a software or configuration error occurs. The configuration is up to the product line.


An alarm is reported and it cannot be determined whether the board needs to be replaced. The alarm may be caused by a board or interface error.

　　 Steady off No error

ACT Green Steady on The board is working in the active state.

1. In dual-mode applications, both the main control boards work in active mode. If this indicator is blinking at the frequency of 4 Hz, the board is an active main control board.

2. During tests, this indicator is on only when the board is working in the active mode.

　　 Steady off

The board does not provide services because it is not working in the active state or the software running on it has not been activated. For example, the board has not been configured or has been manually blocked.

　　 At the frequency of 4 Hz OML link disconnection


The board is being tested. For example, a USB flash drive is used for an RRU VSWR test. If an upgrade is carried out using the USB flash drive, this indicator does not indicate it.

　　At the frequency of 4 Hz (blinking for 2 seconds and then off for 2 seconds)

The service is not ready. For example, the cell or service link is not ready or a fault that requires onsite troubleshooting occurs.


Indicator Functions

Label Color Blinking Frequency Meaning Remarks

CPRIxRed or green

On (green) CPRI links are connected and normal.

　

On (red)

The optical module fails to receive or send data. Examples of the possible causes:− The optical module is faulty.− The optical fiber is disconnected.

Blinking in red at 4 Hz The RRU connected over the CPRI link has a hardware error.

Blinking in red at 0.5 Hz

− CPRI unlock because dual-mode clocks are mutually locked or the transmission rates at the CPRI interfaces do not match each other. To solve this problem, rectify system configurations.

− The RRU connected over the CPRI link reports a VSWR alarm because a test is being carried out using USB flash drives.

OffThe SFP module is not in position or the optical module is powered off.

Thank youwww.huawei.com

Thank Youwww.huawei.com

Training Document_LTE Hardware Operation and Maintenance-20130630-A-1.0

Documents

Transcript of Training Document_LTE Hardware Operation and Maintenance-20130630-A-1.0