Cisco ONS 15310-CL, Руководство по устранению неисправностей

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Cisco ONS 15310-CL and Cisco ONS 15310-MA Troubleshooting Guide, R7.0
78-17235-01
Chapter 1 General Troubleshooting
1.11.2 Faulty Fiber-Optic Connections
e.
Verify that the power level falls within the range specified for the card; refer to the
Cisco ONS 15310-CL and Cisco ONS 1310-MA Reference Manual for information.
Step 4 If the power level falls below the specified range:
a.
Clean or replace the fiber patchcords. Clean the fiber according to site practice or, if none exists,
follow the procedure in the
Cisco ONS 15310-CL and Cisco ONS 15310-MA Procedure Guide . If
possible, do this for the OC-N port you are working on and the far-end ONS 15310-CL or
ONS 15310-MA.
b.
Clean the optical connectors on the port. Clean the connectors according to site practice or, if none
exists, follow the procedure in the
Cisco ONS 15310-CL and Cisco ONS 15310-MA Procedure
Guide . If possible, do this for the card you are working on and the far-end node.
c.
If the power level still falls below the specified range with the replacement fibers and replacement
card, check for one of these three factors that attenuate the power level and affect link loss (LL):
• Excessive fiber distance—Single-mode fiber attenuates at approximately 0.5 dB/km.
•
Excessive number or fiber connectors—Connectors take approximately 0.5 dB each.
• Excessive number of fiber splices—Splices take approximately 0.5 dB each.
Note These are typical attenuation values. Refer to the specific product documentation for the
actual values or use an optical time domain reflectometer (OTDR) to establish precise link
loss and budget requirements.
Step 5 If no power level shows on the fiber, the fiber is bad or the transmitter on the optical port failed. Complete
the following steps:
a.
Check that the Tx and Rx fibers are not reversed. LOS and EOC alarms normally accompany
reversed Tx and Rx fibers. Switching reversed Tx and Rx fibers clears the alarms and restores the
signal.
b. Clean or replace the fiber patchcords. Clean the fiber according to site practice or, if none exists,
follow the procedure in the
Cisco ONS 15310-CL and Cisco ONS 15310-MA Procedure Guide . If
possible, do this for the card you are working on and the far-end card.
c.
Retest the fiber power level.
Tip Most fiber has text printed on only one of the two fiber strands. Use this to identify which fiber is
connected to Tx and which fiber is connected to Rx.
1.11.2.1 Crimp Replacement LAN Cables
You can crimp your own LAN cables for use with the system. Use #22 or #24 AWG shielded wire with
RJ-45 connectors and a crimping tool.
Use a cross-over cable when connecting an ONS 15310-CL or ONS 15310-MA to a hub, LAN modem,
or switch, and use a LAN cable when connecting a node to a router or workstation.
Figure 1-5 shows the layout of an RJ-45 connector.