[c-nsp] GSR OC3 Eng0 to Eng3

[Lamar Owen]

On Tuesday 14 April 2009 11:44:41 Pete Templin wrote:
> Lamar Owen wrote:
> > It's also possible the ADM is sending you a too-hot signal; you can
> > simulate an attenuator for testing by slightly pulling the SC for the
> > receive out; this simulates an air-gap attenuator.  If you can get an
> > improvement with a slight air-gap, it may be too hot from them to you,
> > and you'll need to attenuate.

> Is it possible for the signal to be too hot for an Engine 3 card, while
> not too hot for an Engine 0 card?  We had none of these OSPF events
> before switching cards.  Unfortunately, I wasn't checking for PSE before.

Hmm, engine 3 is using an SFF transceiver, but engine 0 an SC transceiver, so 
I would guess it's possible.  Although the link budgets and power levels are 
documented as being the same ( 
http://www.cisco.com/en/US/docs/routers/12000/gsr_linecards/pos_lc/installation/guide/16412pos.html#wp652319 
).  Both are intermediate reach cards, right?  The engine 3 isn't a long reach 
by chance?  I'm successfully using a 10 meter OC3 SM IR link between a 7609 
OSM and an engine 0 4xOC3 IR, and it just works.

> >  So it could be the interstital hop clock slipping.

> My suspicion is the carrier-carrier handoff, though I'm quick to remind
> myself that the OSPF problems only showed up when we switched cards.

What sort of failures prompted the card switch?

-- 
Lamar Owen
Chief Information Officer
Pisgah Astronomical Research Institute
1 PARI Drive
Rosman, NC  28772
http://www.pari.edu