[c-nsp] Strange T3 failure on 7206

[Seth Mattinen]

On 1/18/2011 09:52, Jay Hennigan wrote:
> We got an alarm that a T3 to a customer was down.  PE router showed
> interface up, line protocol down.  CE router showed down/down.  Provider
> side goes to an Adtran Opti-mux out OC-12 to Verizon, customer end is a
> Verizon mux on premise.
> 
> Called Vz and they claimed it was CPE, they saw "idle loop" towards our
> 7206 CE router.  We shut/no-shut the interface and rebooted the 7206, no
> joy.  I'm not familiar with the term "idle loop", we were showing
> receive LOS and sending RAI.
> 
> Customer IT guy came on site and saw CLOS on Verizon mux, alarm light on
> 7206.  He disconnected the cable and put a coax loop towards the 7206.
> Interface came up-looped right away.
> 
> Reconnected to Verizon mux and everything came back up nice and happy.
> That's what is bugging me.  Circuit has been running fine for months.
> 

I had a T3 card get randomly confused a few months ago and wouldn't
responding to commands properly. Ended up doing an OIR on it to reset it
and called the whole thing "weirdness happens".

Mine was off a Verizon OC-12 to Adtran OPTI-6100 mux (with OC-3, DS3,
and DS1 cards).

~Seth