Spring time fiber cuts (was Re: fiber cut 19 May/PM -> 20 May /AM) (fwd)
Majdi S. Abbas
msa at samurai.sfo.dead-dog.com
Mon May 24 04:00:22 UTC 2004
On Sun, May 23, 2004 at 02:05:36PM -0700, Randy Bush wrote:
> and telcos usually do. but they almost always tell you it's protected.
> force them to test, or pull one side yourself. and repeat the test every
Actually Randy, I would say 85% of the APS problems I've
had were not due to a missing protect, but the inverse.
There are a couple of carriers out there that insist on putting
protects on everything....including circuits explicitly ordered without
them. The best part is when they proceed to put hard loops on the
protect you didn't order, and someone reloads a router. The circuit fails
over to the looped protect, taking it down until you find someone that can
locate which portion of the loop went to protect and take it out.
Rinse and repeat for a different portion of the loop that wasn't
supposed to have a protect every time anything at all takes the circuit
down. Of course, since the circuit was ordered 'without' a protect, the
telco themselves doesn't know it has a protect path. This is always fun
to get them to troubleshoot. :)
It's worth noting that just because you have a working protect
doesn't mean it isn't wdmed or muxed onto the same fiber. If it is
supposed to be a widely divergant path, latency can provide a clue,
but in the majority of cases as the customer you can't really tell if
they've given you the protect you asked for or not.
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