Huawei HG8245T Router Manual PDF (Setup & Configuration Guide)

Page 401 / 429 Scroll up to view Page 396 - 400

Figure 5-19

Too large optical power difference

Step 3

Add a 10 dBm attenuator before ONU 0. Other ONUs successfully go online.

Step 4

Such a fault does not recur in the next week.

----End

Suggestion and Conclusion

The difference between the ONU Max. receive optical power and the Min. receive optical power

should be smaller than 15 dBm, as specified in the protocol. That is, the attenuation difference

between any two ONUs connected to a PON port must not be larger than 15 dBm.

5.8.2 ONU Profile Mismatch

The ONU profile mismatch failure is a fault in which an ONU connected to a PON port of an

OLT can go online successfully, but the queried

Match state

of the ONU is displayed as

mismatch

by running the

display ont info

command on the OLT.

TC-C6000 The Match State Is mismatch Because of the Inconsistency Between the

Number of GEM Ports in the Capability Set Profile and the Number of GEM Ports

Supported by an ONU

This topic describes how to troubleshoot the fault when the

Match State

of an ONU is

mismatch

because the number of GEM ports in the ONU capability set profile delivered by the

OLT is inconsistent with the number of GEM ports supported by the ONU.

Fault Type

GPON service

Keyword

Capability set profile

mismatch

GEM port

EchoLife HG8010/HG8240B/HG8245T/HG8247T GPON

Terminal

Service Manual

5 Maintenance and Troubleshooting

Issue 01 (2011-10-18)

Huawei Proprietary and Confidential

393

Page 402 / 429

Fault Description

Version: MA5600T V800R007C01 and earlier versions only, and not for V800R008 and later

versions.

After an ONU is added to the OLT in a new office, an engineer runs the

display ont info

command on the OLT to query the ONU. The

Match State

of the ONU is always

mismatch

.

Alarm Information

None

Cause Analysis

After the ONU is added, if the ONU can go online normally, and the

Run State

and

Match

State

of the ONU are

up

and

mismatch

respectively, the possible cause is that the actual

capability of the ONU is inconsistent with the capability set profile bound to the ONU, or the

ONU is faulty.

Procedure

Step 1

Check the ports of the ONU on site. It is found that capability set profile configured on the OLT

is consistent with the actual capability of the ONU. Run the

display ont capability

command

to check the ports of the ONU and the parameters such as T-CONTs on the OLT. It is found that

the ports of the ONU and the parameters are consistent with the actual configurations.

Step 2

Consult ONU technical manuals. It is found that the ONU supports up to 128 GEM ports. Only

32 GEM ports, however, can be configured in the capability set profile by the OLT. Therefore,

the parameter about the number of GEM ports is set differently. As a result, the

Match State

of

the ONU is

mismatch

.

----End

Suggestion and Conclusion

Though this parameter does not affect services, the configurations cannot be delivered to the

ONU after the ONU is reset. You can run the

ont resume resource

command to configure the

recovery policy of the ONU. If the actual capability of the ONU is different from the capability

set profile bound to the ONU, the OLT excludes the management commands that are beyond

the actual hardware capability, and delivers only the management commands within the ONU

hardware capability according to the hardware capability parameters reported by the ONU.

5.8.3 Failure to Automatically Discover an ONU

The ONU auto discovery failure is a fault in which an OLT fails to automatically discover an

ONU after the ONU is powered on.

TC-C6004 Certain ONUs Fail to Be Auto Discovered on the OLT Because of Very

Short Maximum Registration Distance

This topic describes how to troubleshoot the fault when certain ONUs fail to be auto discovered

on the OLT because the maximum registration distance configured on the OLT is very short.

EchoLife HG8010/HG8240B/HG8245T/HG8247T GPON

Terminal

Service Manual

5 Maintenance and Troubleshooting

Issue 01 (2011-10-18)

Huawei Proprietary and Confidential

394

Page 403 / 429

Fault Type

ONU auto discovery failure

Keyword

Registration failure

Fault Description

Certain ONUs connected to a PON port of an OLT in an office can be auto discovered on the

OLT successfully, but certain ONUs fail to be auto discovered on the OLT.

Alarm Information

None

Cause Analysis

l

The hardware of the ONUs is faulty.

l

The ports of the PON board do not work normally.

l

The data configuration of the system is incorrect, and the maximum distance for registering

the ONUs is short.

Procedure

Step 1

The fault occurs on multiple ONUs, and the fault persists after the ONUs are replaced. This

indicates that the hardware of the ONUs is normal.

Step 2

Certain ONUs connected to the PON port can register with the OLT normally, and the ONUs

work stably. This indicates that the PON board is normal.

Step 3

After check, it is found that the ONUs that fail to register with the OLT are far from the OLT,

and the physical distance ranges from 3 km to 5 km. The ONUs that are 1 km away from the

OLT do not encounter the fault.

Step 4

Run the

display port info

command to view the maximum registration distance of the PON

port. It is found that the maximum registration distance is 2 km.

Step 5

Run the

port

portid

range max-distance

command to change the maximum registration distance

of the PON port to 20 km. As a result, the fault is rectified.

----End

Suggestion and Conclusion

The maximum registration distance of the system is 20 km by default. Do not change the

registration distance at discretion. By default, the minimum and maximum registration distances

of the ONU are 0 km and 20 km respectively, and the configuration granularity is 1 km.

EchoLife HG8010/HG8240B/HG8245T/HG8247T GPON

Terminal

Service Manual

5 Maintenance and Troubleshooting

Issue 01 (2011-10-18)

Huawei Proprietary and Confidential

395

Page 404 / 429

TC-C6015 An ONU Fails to Be Auto Discovered on an OLT Because the Actual

Distance Between the ONU and OLT Is Longer Than the Preset Maximum Distance

This topic describes how to troubleshoot the fault when an ONU fails to register with an OLT

because the actual distance between the ONU and OLT is longer than the preset maximum

distance.

Fault Type

ONU auto discovery failure

Keyword

Registration failure

Fault Description

An ONU is connected to an OLT directly through an optical fiber. The ONU fails to be auto

discovered on the OLT.

Alarm Information

None

Cause Analysis

l

The optical path attenuation is very large.

l

The data configurations of the ONU or OLT may be incorrect.

Procedure

Step 1

Use an optical power meter to measure the optical power of the PON ports of the OLT and the

remote ONU. The optical attenuation is about -12 dB, which is within the normal range. This

indicates that the optical path is normal.

Step 2

Connect an ONU at the local end to the OLT. It is found that the ONU can be auto discovered

on the OLT, which indicates that the PON ports on both sides of the ONU and OLT are normal.

Step 3

The ONU at the local end can be auto discovered on the OLT whereas the ONU at the remote

end fails to be auto discovered on the OLT. Therefore, it is suspected that the distance between

the ONU and OLT is very long. The maximum distance supported by the OLT is 20 km by

default. Run the

port

portid

range max-distance

command to change the maximum distance

supported by the OLT to 30 km. As a result, the fault is rectified.

----End

Suggestion and Conclusion

It is not recommended that the distance between an OLT and ONU exceed 20 km. Otherwise,

if the distance is very long, the ONU that can be auto discovered on the OLT fails to be auto

discovered on the OLT due to deteriorated surroundings.

EchoLife HG8010/HG8240B/HG8245T/HG8247T GPON

Terminal

Service Manual

5 Maintenance and Troubleshooting

Issue 01 (2011-10-18)

Huawei Proprietary and Confidential

396

Page 405 / 429

TC-C6308 The ONU Cannot Be Automatically Found Because the Optical

Attenuation Is Excessively High

This topic describes how to troubleshoot the fault when the ONU cannot be auto discovered

because the optical attenuation is excessively high.

Fault Type

GPON service

Keyword

Optical Attenuation

Fault Description

All LEDs of the ONU are normal. Enable the auto discovery function and it is found that the

OLT cannot auto discover the ONU.

Alarm Information

None

Cause Analysis

l

The ONU is faulty.

l

The configuration on the OLT is improper.

l

The optical path is faulty.

Procedure

Step 1

All LEDs of the ONU are normal. Therefore, the problem is not caused by the faulty optical

path.

Step 2

Use an optical power meter to check segment by segment the optical power of each connection

point. It is found that optical attenuation for a segment of optical fiber between the ODF in the

telecommunications room and the optical splitter reaches –13 dB. As a result, the optical

attenuation after the optical splitter reaches –30 dB, which is lower than the minimum activation

optical attenuation (–27 dB) of the ONU. Therefore, the ONU cannot be auto discovered. After

the optical fiber is replaced, the fault is rectified.

----End

Suggestion and Conclusion

The optical attenuation of the optical path between the ONU and the OLT should be within the

range of 15–25 dB.

TC-C6210 ONU Auto Discovery Failure Because of Too Long Fibers

This topic describes how to troubleshoot the fault of ONU auto discovery failure.

EchoLife HG8010/HG8240B/HG8245T/HG8247T GPON

Terminal

Service Manual

5 Maintenance and Troubleshooting

Issue 01 (2011-10-18)

Huawei Proprietary and Confidential

397

Rate

Popular Huawei Models

Famous Router IPs

Famous Router Companies

Bookmark Our Site

Share