1-96
Cisco ONS 15454 DWDM Troubleshooting Guide, R7.0.1
78-17742-02
Chapter 1 General Troubleshooting
1.13.2 VOA Failure Scenarios
e. Click the Provisioning > Optical Chn: Optical Connector X > Parameters tabs and identify the
proper channel (wavelength).
Note X is number (1 to 4) of the proper multifiber MPO connector that manages the alarmed
channel (wavelength).
f. Decrease the attenuation on the VOA to the minimum (0 dB) to enable channel startup. To perform
this in field adjustment:
• Read the VOA Attenuation Ref value for the channel (wavelength).
• Enter the same value into the VOA Attenuation Calib field as that of the VOA Attenuation Ref
field, but with the opposite sign (the algebraic sum of the two contributions must be equal to
zero).
• Click the Apply button. If the LOS-P alarm persists, continue with this procedure. Otherwise,
the problem has been corrected.
g. Click Circuits.
h. Recreate the OCHNC circuit and verify that Circuit Status field reports DISCOVERED and the state
is IS (Unlocked).
i. If the LOS-P alarm has not cleared, continue with Step 10. Otherwise, the problem has been
corrected.
Step 10 To unambiguously pinpoint the root cause of the alarm, verify the proper cabling of the alarmed
ADD_RX port on the 32MUX-O card:
a. The ADD_RX port of the alarmed 32MUX-O must be connected to the DROP_TX port of the
coupled 32DMX-O card on the opposite side of the node using two MPO-LC multifiber cables.
Note A patch-panel tray is normally used to manage fiber connections (for patch-panel cabling details, refer
to the “Turn Up a Node” chapter in the Cisco ONS 15454 DWDM Procedure Guide).
b. Verify that the power value coming out of DROP_TX port of the coupled 32DMX-O card is correct:
• In card view, click the Provisioning > Optical Chn: Optical Connector X > Parameters tabs.
Note X is number (1 to 4) of the proper multi-fibers MPO connector that manages the alarmed
channel (wavelength).
• The Power field value must be the same as that in the VOA Power Ref field. If it is not, take the
appropriate corrective action for the alarm according to Chapter 2, “Alarm Troubleshooting.”
c. Check and clean the LC fiber fan-out according to site practice. The fiber numbers (1 to 8) must
correspond to the wavelength managed.
d. Repeat Step c for the MPO-LC multifiber cable coming out of the DROP_TX port of the coupled
32DMX-O card.
e. Check and, if necessary, clean the LC-LC adapter.
f. If necessary, replace and bad devices (maximum tolerance is 1 dB).
To Next Page
Loading...
Need help?
General
