Traceroute issue - MPLS CE router replys 2 hops on ingress &

From: Jerry Wang (jerry-wang@rogers.com)
Date: Wed Aug 31 2005 - 13:15:53 GMT-3

• Next message: gladston@br.ibm.com: "DHCP based on hostname"
• Previous message: Tony Schaffran: "RE: OT default gateway"
• Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] [ attachment ]

Hi Guys,

Please help to explain the following traceroute issue I found in my lab:

I have 2 Routers R1 & R2 on two sites, both are connecting to MPLS/VPN cloud. When I do traceroute from R1 to R2, I found the first 2 hops reflect the ingress and egress interfaces on the same CE1 router, which is connecting to R1. Please see following details:

Traceroute path (on R1, do traceroute to R2's loopback address):

R1 -- CE1 -- PE1 -- PE2 -- CE2 -- R2

Tracing output:

1. CE1_ingress_int
2. CE1_egress_int
3. CE2_ingress_int
4. R2_ingress_int

FYI: the /30 link route between CE1 & PE1 is not advertised to R1. not sure if this affects or not.

I have no access to to the Telco CEs & PEs , I assume it might be related to CE1's MPLS traceroute configuration. Or it might be related to the ttl propagation between the IP & MPLS domain?

Your help is highly appreciated!

Thanks and best regards

Juntao
Network Engineer

• Next message: gladston@br.ibm.com: "DHCP based on hostname"
• Previous message: Tony Schaffran: "RE: OT default gateway"
• Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] [ attachment ]

This archive was generated by hypermail 2.1.4 : Sun Sep 04 2005 - 17:01:20 GMT-3