bgp and traceroute

Unanswered Question
Jul 4th, 2002
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Hi all,

I am having multiple internet providers and running BGP with all of them.

Traceroute packets are ping packets with incrementing TTL value. I can know the forward path from my client to the destination i.e ping request path. But i am wanting to know the ping reply path i.e the reverse path from the remote client to reach to me. Elaborately, i want to know the reply is coming through which of my internet provider.

Thanks in advance..



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yusuff Thu, 07/04/2002 - 22:34
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There is no reverse traceroute you can do.

Only way to check is "debug ip packet detail"; which ingress interface the packet arrived to you, in that way you know which ISP path did it take to enter your router.


ping reply packet from source below is entering my router using ingress interface FastEthernet0.

2d00h: IP: s= (FastEthernet0), d=, len 100, rcvd 4

2d00h: ICMP type=8, code=0

2d00h: IP: s= (local), d= (FastEthernet0), len 100, sending



sun816 Thu, 07/04/2002 - 23:03
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There is no reverse msg traceroute.

But why not use a agent capturer at remote site LAN and grab the icmp reply

packets sourced from remote site?

nuno.morais Tue, 07/09/2002 - 04:53
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You can try to use the "record route" option.

Hope this helps.



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