Huawei SmartAX MA5612, Maintenance Manual

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Fault Location Location Analysis Possible Causes
OLT The Internet access rates on all
ONU ports are low. The DBA bandwidth that the OLT
allocates to the ONU is insufficient.
Upper layer
BRAS Only certain users' Internet access
rates are low; the services of other
users on the BRAS are normal. Certain users' Internet access rates
are restricted on the BRAS.
CAUTION
To facilitate fault report, save the results of the following steps.
Procedure
Step 1 Determine the fault range when identifying the fault causes.
l If the Internet access rates of only certain users on the ONU are low whereas the rates of
other users are normal, go to
Step 2 .
l If the Internet access rates of all users on the ONU are low, go to Step 7 .
Step 2 Check the user terminal.
1.
Replace the user's PC and test whether the Internet access rate is normal.
l If the Internet access rate is normal, the fault is on the PC. Check whether the NIC in
the user's PC is faulty, the PC is infected with viruses, the PC is slow to respond after
running for a long time, or the PC's configuration is low. Then, go to
Step 11 .
l If the Internet access rate is low, go to Step 2.2 .
2. Replace the user terminal, and then check whether the Internet access rate is normal.
l If the Internet access rate is normal, go to Step 11 .
l If the Internet access rate is low, go to Step 3 .
Step 3
Check whether the line between the ONU and the user terminal is normal.
1.
Check whether cyclic redundancy code (CRC) loss occurs on the subscriber line.
l If CRC loss occurs on the subscriber line, go to Step 3.2 .
l If CRC loss does not occur on the subscriber line, go to Step 4 .
NOTE
Query the statistics of the faulty port multiple times (recommended: 10 times) and then compare the
statistics to check whether packet loss occurs on the subscriber line. The query interval is 20s.
Run the display port statistics portid command on the ONU to query all the performance statistics of the
subscriber line after the subscriber line is initialized. Then, check whether the number of CRC error frames
increases. If it increases, packet loss is occurring on the subscriber line.
2. Check whether the physical line between the ONU and the user terminal is connected
properly or whether the line is old. Reconnect the line properly or replace the line as needed.
Then, check whether the Internet access is normal.
l If the Internet access is normal, go to Step 11 .
SmartAX MA5612 Multi-service Access Module
Maintenance Guide 5 Troubleshooting Services Transmitted Through a GPON
Port
Issue 01 (2012-07-25) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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