[c-nsp] NX-OS MPLS not answering to traces

[Bernhard Schmidt]

Phil Mayers <p.mayers at imperial.ac.uk> wrote:

Hello Phil,

>> Also a good guess, but it's a fresh installation of 6.1(2) and I've
>> verified that there is indeed a CoPP entry for "match protocol mpls".
>> The class is not dropping a lot of traffic.
> I'm assuming you're aware of the way traceroute works for P-routers, 
> specifically that the generated ICMP packet is sent onwards down the 
> original LSP then turned around by the far-end PE. Have you (or can you) 
> verify that this packet is being generated (SPAN on the next-hop input 
> interface)? Perhaps the far-end PE is dropping the packet because it 
> dislikes something about it, something specific to the NX-OS boxes?
>
> Determining whether this ICMP is being generated seems a good first step.

Yes, I'm aware of how traceroute works. Will take me a day to get a
sniffer there, but I'll check. Problem happens with all combinations of
NX-OS/IOS head-end and far-end PEs and regardless of the ttl-expiration
pop setting.

Bernhard