RE: MPLS propagate-ttl question

You are seeing:

R3 - left interface
R4 - right interface
R5 - left interface

"no mpls ip propagate-ttl [forwarded]" that you added prevented you from
seeing:

R2 - left interface

You will still see VPNv4 label that R4 popped

Regards,

Roman Rodichev
6xCCIE #7927 (R&S, Security, Voice, Storage, Service Provider, Wireless)
Instructor, Content Developer
ieMentor Corporation http://www.iementor.com
Y!M: roman7927

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of Ivan
Sent: Sunday, November 01, 2009 12:53 PM
To: Cisco certification
Subject: MPLS propagate-ttl question

I have topology like this:
R1 -- R3 -- R2 -- R4 -- R5

where R2, R3 and R4 are LSR routers (R3 and R4 are PE, and R2 is P router),
and R1 and R5 are customer routers.
On routers R2, R3 and R4 I issued no mpls ip propagate-ttl
forwardedcommand. How come that when I'm doing traceroute from R1 to
R5 I still se
info about MPLS labels in provider's network:

R1#traceroute 5.5.5.5 source loopback 0

Type escape sequence to abort.
Tracing the route to 5.5.5.5

  1 10.1.13.3 4 msec 0 msec 4 msec
  2 10.1.45.4 [MPLS: Label 405 Exp 0] 0 msec 4 msec 0 msec
  3 10.1.45.5 28 msec * 28 msec

Is that normal behavior? Can we avoid provider's PE routers from traceroute
output, and here 10.1.13.3 is R3, 10.1.45.4 is R4 (PE routers) and 10.1.45.5
is CE.

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Received on Sun Nov 01 2009 - 13:05:31 ART