[c-nsp] UDLD enabling port prematurely?

[Victor Sudakov]

Peter Rathlev wrote:
> > [...] I need some sort of point-to-point L2 link fault management
> > between the switches.
> >  
> > Is UDLD suitable for this purpose? I have experimented a bit with
> > "udld port aggressive" and have found out the following strange
> > thing.
> > 
> > When the physical link goes down, UDLD detects this condition and
> > shuts the switch interface down. However, after several minutes, the
> > interface goes up again with "%PM-4-ERR_RECOVER: Attempting to recover
> > from udld err-disable state on Gi0/17". The interface is up even
> > though "Current bidirectional state: Unknown", and seems to be in the
> > STP forwarding state.
> 
> This is because UDLD errdisable recovery has been enabled. You can
> disable it with:
> 
>    no errdisable recovery cause udld
> 
> Problem is that you have to intervene manually to enable the interface
> after service has been restored. 

I may be already unable to reach the switch remotely to intervene
manually, after the interface has been errdisabled for good.

> But at least you will not have loops.
> 
> I'm not aware of a more elegant solution to your problem, but I'm
> interested in hearing about one.

What if I try the non-aggressive UDLD, would it make any difference?

-- 
Victor Sudakov,  VAS4-RIPE, VAS47-RIPN
sip:sudakov at sibptus.tomsk.ru