After adding the 40G lambda over existing 10G lamdas, BEFFEC_EXC alarm is appear on OTU's.
1)Check the Span loss in all section of this link.span loss is under design.
2)complete the link commissioning as per standard, but alarm is still on.
3)Check the optical power of NS3 it was in between -6 to -10.
3)Jack out jack in the NS3 card but still problem is not resolved.
4)Replace the DCM-A at recieving end where BEFFEC_EXC was observed, all alarm got cleared
The cause of BEFFEC_EXC which reported by NS3 cards
1)The NS3 hardware is faulty.
2)Getting Low/ high optical power on NS3.
3)The XCS board has some problem.
4)The commissioning of the particular link is not ok, or having fiber losses in any section of the link.
5)DCM Configuration is not ok.
We should never ignore the DCM Configuration when we added 40G lambda over existing lambda