[c-nsp] link flaps

[Oliver Boehmer (oboehmer)]

> 
> Router R1 --------------Ethernet
> Cable-----MUX----------------MUX-----------Ethernet Cable-------Router
> R2
> 
> I have backup link but conbvergence takes time and packet drops. The
> area is remote area where I have this link , so link flaps are quite
> normal.
> I was thinking If links flaps 3 or 4 times in say 1 min , I put the
> link in BAD state and not use it .Instaead I use backup link.If
> prinary link is ok for 1 hr. I again use it...
> 
 
IP event dampening would be the feature of choice, and you could find
settings to take down the link for routing after a few flaps per minute
("dampening 30 200 1800 120"), but the dampening algorithm wouldn't
allow it to stay down for so long as an hour (unless the link continues
to flap). With those settings, the link would come back up ~2 minutes
after the flapping stops..
If you need to keep it down for much longer, EEM scripting would be an
alternative (I think a complex one, not an EEM expert)..

	oli