[j-nsp] Proper Break of MPLS RSVP Ring

[Ben Dale]

Hi Levi,

> On 17 Jul 2015, at 5:22 am, Levi Pederson <levipederson at mankatonetworks.net> wrote:
> This is displaying it self in my output by not having an RSVP Neighbor
> (neighbor down hellos sent) between C&D (and therefore sending my traffic
> inefficiently 3/4 way around the ring instead of the 1/4 hop it could.
> Last bit of information is that D sees C as a neighbor but is down.  C does
> not even see D as a neighbor at all.

This sounds like an L2 issue, or perhaps a misconfiguration - all nodes should be RSVP neighbours in order to be able to signal LSPs across those interfaces.

Check your protocols rsvp config for the logical interfaces between D.

Use monitor traffic interface <D-C interface> on D to confirm that RSVP is being sent out of the box.

Check any control-plane filtering/firewall filters you have configured on C (though it seems to be receiving just fine from B).

> I'm wondering how RSVP breaks that link.  All the documentation I can find
> are focused on LSP validation/creation and not on Link Breaks to stop layer
> 2 loops (is my assumption).  If one of my intervening links goes own I
> would like to correct it and then move the break to the specified point.
> But the RSVP documentation is rather...limited to only LSPs if I am reading
> it correctly.

RSVP won’t break the link to stop loops (the LSPs will carry service labels which may not even be L2 services), it will simply establish the LSP across the best/shortest path between endpoints (based on your TE settings), and if this becomes unavailable (and depending on your configuration) it will simply re-establish over any alternate path (which it sounds like is working well).

Cheers,

Ben