[lug] connection path

[Chuck Wiechman]

You can tell by the mac address which router a packet came from.


On Mon, 5 Nov 2001, Kyle Moore wrote:

> If I have a system that sits on a network that two routers serve, is there
> any way to tell which one a connection came through? I have two T1's from
> different providers that come through two different routers. Both of the
> routers internal interfaces are on the same subnet. If a connection is
> made from the a machine on the net to a server is there any way I can tell
> from the monitoring box which router the connection was made? The key is
> using only the monitoring box to identify this info instead of info from
> any other system.
> 
> I ran tcpdump -n -w logfile and I can see the arp requests but that is
> about it.
> 
>             |                  |
>             |                  |
>         ____|___            ___|___
>         |router|            |router|
>         --------            --------
>             |                  |
>             |                  |
>         ----------------------------
>         |         switch           |
>         ----------------------------
>                   |        |
>                   |        |
>                -------    ---------
>                |box a|    |monitor|
>                -------    ---------
> 
> 
> ---
> Kyle Moore
> 
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