[CLUE-Tech] ARP problems with Linux...

[Brandon N]

--- Tim Russell <tim.russell at ilg.com> wrote:
> I guess one question to ask is, /why/ do you have both Ethernets on
> the same
> network?  
My question too, I had a hunch so I did a little investigating.
here is my test network:

Streaker                       Rama
eth0 -------------------------|eth1
                              |
DSL |-------------------------|eth0

Streaker does not have a default route, but I added a route to
Rama:eth0 through Streaker:eth0

I did a ping, and I got a response
arp -a showed that eth1 responded with it's HW address, even though the
IP was for eth0.

So basically in your case the external interface is responding saying,
I'm not that card, but I know how to get there, so give me the packet.
I wonder is it pings that are failing, or something else, and is it
being routed further or is that machine the final destination.  Are you
using ipchains?

I see a couple possible solutions.
buy a 4 port hub and separate the interfaces physically
only use one interface, with both IP on a single NIC
set HW addresses using /etc/ethers
figure out if there is a way to turn off this response (probably in
/proc)