Re: Weird MPLS Label Switching Problem

One thing I forgot to mention. For CE-CE trace there is no label seen in the
traceroute but trace completes properly and I can ping between the CEs
normally

Thanks

On Sun, Feb 27, 2011 at 12:07 AM, Malik Nouman Ahmad <djmalik_at_gmail.com>wrote:

> Hi,
>
> I was studying MPLS VPN and while working on an example I am facing some
> strange issue
>
> The connectivity is CE1 - PE1 - P1 - P2 - PE2 - CE2
>
> PE1(.1) - CE1 (.2) with subnet 172.16.1.0/24 with VRF A (RD=RT=1:1)
> PE2(.1) - CE2 (.2) with subnet 172.16.2.0/24 with VRF A (RD=RT=1:1)
>
> PE1 & PE2 have MPLS VPN set up and I can see labels for everything when I
> check "show mpls forwarding" on the PEs
>
> when I trace from PE1 to CE2 I can see labels being switches properly using
> the following command
> trace vrf A 172.16.2.2 source 172.16.1.1
>
> but when trace from CE1 to CE2, there are no labels whatsoever
> trace 172.16.2.2 source 172.16.1.2
>
> Same thing is happening in the reverse direction (i.e. trace from CE2 to
> CE1). I have done several examples previously and never faced such issue.
> Instead of doing it all over again I want to troubleshoot the problem for
> learning purpose
>
> Can anybody suggest how to troubleshoot this problem? I have applied "no
> mpls ip propagate-ttl" just to see if it was working and it worked
>
> Please advise what should I do?
>
> Thanks,
> Malik

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Received on Sun Feb 27 2011 - 00:10:08 ART