After a day and a half uptime, it seems FEC errors are a problem ...
FECs are not a problem Jamie in themselves, as they (bit errors) have all been recovered successfully.
If they weren't, you would be seeing non-zero CRC and ES counts.
Recall that your line has an interleaving depth of 2177. This is to allow the recovery of bit errors caused by (impulse) noise bursts that might last as long as 9ms (the value of your INP). Since every line has some noise some of the time, it is inevitable that you will get a non-zero FEC count. This is the way it is supposed to work, and demonstrably here, it is.
Just to make you feel better, my INP is 3ms, and my interleaving depth is 1233, but my syncs rates are ~ double yours DS at ~78/20 (hence ~twice as many DS bits in the same time period). Here are my FEC counts for the last 24hrs:
Previous 1 day time = 24 hours 0 sec
FEC: 607430 299
CRC: 28 72
ES: 5 65
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
So, in a relative world, my line is much noisier (18x) than yours.
(Assuming I've got my sums right ...) My BER is ~900*10^-10, whereas your BER is ~50*10^-10.
A
reasonable target BER is ~1*10^-10.
[Edited to compare BERs]
I hope this helps. Wouldn't want you to become one of the 'worried well'?!
If there is anything to investigate, it is the source of this REIN (and the bit loadings that B*Cat is currently attending to, I trust
) Perhaps a passing black sheep might offer the benefit of his experience with the former?