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New Member

Why I can't reach a distant LAN IP of a router, from a PC and not from a router?

Hi,

When I try to trace the LAN of a router from another cisco router, it stops on the WAN, but when trying from a  Win7 PC it reaches.

Is there a reason?

Thanks.

6 REPLIES

Why I can't reach a distant LAN IP of a router, from a PC and no

It depends on what it uses as the source address when you traceroute from a Router.

New Member

Why I can't reach a distant LAN IP of a router, from a PC and no

The wan. And there is a public IP there

Hall of Fame Super Blue

Why I can't reach a distant LAN IP of a router, from a PC and no

Have you checked that there are routes on the return path for the router IP.

Jon

New Member

Why I can't reach a distant LAN IP of a router, from a PC and no

Well, I don't have access to the distant router to perform a bi-directional, but what I understand is that if the ping responds successfully is because both routes are know, correct?

The strange is that pinging from a PC it goes correctly.

Why I can't reach a distant LAN IP of a router, from a PC and no

Windows uses icmp for traceroute whereas Cisco uses UDP. Your traffic on the other end may be allowing icmp messages through, but not udp. I believe Linux uses udp as well, so if you have access to a Linux server and this is the cause, you should see the same result as the router does.

HTH,
John

*** Please rate all useful posts ***

HTH, John *** Please rate all useful posts ***
Hall of Fame Super Blue

Why I can't reach a distant LAN IP of a router, from a PC and no

but what I understand is that if the ping responds successfully is because both routes are know, correct?

Yes, but if the PCs IP may be from a different IP subnet than the routers IP so havng routes for the PC's IP does not necessarily mean there are routes for the router's IP.

Jon

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