[c-nsp] 10G and carrier delay

[Saku Ytti]

On (2006-09-26 13:15 +0200), hjan wrote:

Hello,

> anyone has some hints on 12000-SIP-601 with XFP-OC192SR PA and
> carrier-delay?
> I use this 10g interface over dwdm link, Siemens, interface are configured
> with:
> "carrier-delay msec 2" but I've noticed some routing issue, i have dual 10g 
> link and sometime I must issue shut and non shut on one link to reinitialize 
> ospf.
> At the moment i delete "carrier-delay msec 2" and all seems fine.
> Is there anyone with same experience?

You should also use 'dampening' under interface configuration for low
carrier-delay.
TAC said on one case that cisco default is 50ms, which is not true,
as you can probably see, it's 10ms per default, which still,
from my point of view is very low and begs 'dampening'.
I know it used to be 2s (perhaps still is on some platform/interface),
which is insanely long.

I'm running msec 0 on many platforms without any issues thus far,
but I ran it with dampening from day 1.
TAC tells us that it's normal for ethernet interface go up/down
several times when it's coming up, depending not only 
on receiver but also senders transceiver and temperature (the
warmer it is, the longer convergence). And they suggested
not to tune it faster than 20ms (which of course is higher
than their default). However they also said that considerable
amount of transceivers will produce good results with 0 too.

-- 
  ++ytti