Counter-PropagatingLightAffectingOperationof32DMX-Cand32DMX-LCards
Problem
The in-service operation of the 32DMX-C and 32DMX-L cards (with vendor ID 2049 and 2050) can
be seriously affected by the counter-propagating light travelling from the drop ports of the card towards the
COM RX port. This counter-propagating light affects the internal VOA control loop of the vendor-specific
optical module of the 32DMX-C and 32DMX-L cards, leading to an increased optical path attenuation. This
is traffic affecting for all in-service channels.
Possible Cause
The counter-propagating light can be inserted into the 32DMX-C or 32DMX-L card as a
result of incorrect cabling of transponder or line cards to the fiber patch-panel (in particular, swapping
RX with TX patchcords).
Solution
For software releases higher than or equal to 9.0, the vendor-specific optical module on all the cards
is automatically upgraded to a newer version. The vendor ID of the new version of the card is 2051 and can
be viewed at
CTC > Card View > Inventory
tab. This new version of the optical module makes the VOA
control robust to counter-propagating light, thus, minimizing the effects of incorrect cabling during installation
and/or maintenance.
Solution
For software releases lower than 9.0, for new 32DMX-C and 32DMX-L cards that are not already
installed, the vendor-specific optical module on all these new cards is automatically upgraded to a newer
version at the Cisco Spare depots. Once the new card is installed in field, a downgrade of the optical module
will be prevented and the latest optical module version is preserved on the software package. If the 32DMX-C
or 32DMX-L card is already installed, complete the
Corrective Action for Software Releases Lower than 9.0,
to manually fix the problem.
Corrective Action for Software Releases Lower than 9.0
SUMMARY STEPS
1.
If the TXP card is preprovisioned in CTC, but not installed:
2.
Install the TXP card into the receptacle at the back of the designated slot.
3.
Wait for the TXP card to boot completely.
4.
Verify that the Trunk-TX port of the TXP card is in OOS,DSBLD (ANSI) or Locked,disabled (ETSI)
state.
5.
Wire the Trunk-TX/RX port of the TXP card to the fiber patch-panel.
6.
Turn up the TXP card and display card view for the TXP card in CTC.
7.
Click the
Provisioning > Line
tab and choose
IS,AINS
(ANSI) or
Unlocked,automaticInService
(ETSI)
from the Admin State drop-down list for the Trunk-TX port.
8.
Display card view for the 32WSS card.
9.
Click the
Performance > Optical Chn
tab and verify the Power ADD field on the CHAN-RX port of
the 32WSS card connected to the TXP card.
DETAILED STEPS
Step 1
If the TXP card is preprovisioned in CTC, but not installed:
a) Log into CTC.
b) Display card view for the TXP card.
c) Click the
Provisioning > Line
tab and choose
OOS,DSBLD
(ANSI) or
Locked,disabled
(ETSI) from the Admin
State drop-down list for the Trunk-TX port.
Cisco NCS 2000 series Troubleshooting Guide, Release 11.0
97
General Troubleshooting
Counter-Propagating Light Affecting Operation of 32DMX-C and 32DMX-L Cards