Troubleshooting Path Problems; Path Problems On A Commissioned Link - Alcatel-Lucent 9500 MXC User Manual

Chapter 2. 9500 MXC Troubleshooting

Troubleshooting Path Problems

Path Problems on a Commissioned Link

Vol. V-2-6
• NCC software requires approximately three minutes to verify the status and
configuration of all plug-ins and ODUs. When an NCC is withdrawn and
re-inserted during an NCC/NPC protection test, the NCC must be allowed
not less than 3 minutes to complete this task before subsequent NCC
removal. For more information refer to Commissioning, Chapter 1.
• Where dynamic NMS routing is configured, allow not less than 5 minutes
for the 9500 MXC router address-table auto-update to complete.
A path-related problem, with the exception of interference, is characterized by
traffic being similarly affected in both directions. Generally, if you are
experiencing only a one-way problem, it is not a path problem.
A path extends from ODU antenna port, to ODU antenna port.
• Normally a path problem is signalled by a reduced RSL, and depending on its
severity, a high BER.
• Only in worst case situations, such as an antenna knocked out of alignment, will
a path fail completely, and stay that way.
• For weather-related problems, such as rain or ducting, the path problem will
disappear as the weather returns to normal.
Refer to:
• Path Problems on a Commissioned Link on page 2-6
• Path Problems on a New Link on page 2-7
A path problem on an existing link, one that has been operating satisfactorily
may be caused by:
• Weather-related path degradation
If BER alarms are fleeting / not permanent and RSL returns to its normal,
commissioned level after the alarm is cleared, rain, diffraction, or multipath
fading is indicated. Rain fade is the likely cause of fade for links 13 GHz and
higher. Diffraction and multipath/ducting for links 11 GHz and lower. If these
alarms are persistent, there could be a problem with the link design or original
installation.
• Changed antenna alignment or antenna feed problem
If RSLs do not return to commissioned levels after a period of exceptionally
strong winds, suspect antenna alignment.
Also, check the antenna for physical damage, such as may occur with ice-fall.
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