[j-nsp] Could you pls clarify a bit about OAM for link fault management?

[Victor Sudakov]

Chuck Anderson wrote:
> > > > > Something like this should do the trick once you've configured it on both ends:
> > > > > 
> > > > > set protocols oam ethernet link-fault-management action-profile UDLD event link-adjacency-loss
> > > > 
> > > > I have come to the conclusion that 
> > > > 
> > > > "set protocols mstp interface ge-0/0/22.0 bpdu-timeout-action block"
> > > > 
> > > > might do the trick as well if configured on all interfaces connected to
> > > > the MUXes.
> > > 
> > > That would only work on the upstream interface facing the root bridge
> > > where it is expected that it receive BPDUs.  
> > 
> > Still, if I enable "bpdu-timeout-action block" on every interface
> > facing the MUX (and therefore facing each other), I am probably safe?
> 
> In my experiece, if an interface configured with "bpdu-timeout-action
> block" stops receiving BPDUs, it will block :-) I don't recall what
> happens if it never receives a single BPDU initially (as a
> non-root-facing port should experience since it should be sending
> BPDUs not receiving them), 

I guess, in Cisco, the loop guard feature does not block designated
ports. Is it different in Juniper?

> but you are setting yourself up for pain if
> it later does receive a BPDU, then stops receiving them.  There may be
> transient conditions in a MSTP network where this happens.

What exactly problem can arise in this case? A port never coming up? 

Sorry, I cannot quite grasp the idea, could you illustrate?

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