On a Fedora 9 box with multiple Ethernet interfaces, is there a way to have test apps or command shells tied to specific ports, and for those ports to have no routing to each other?

For example, if you have eth1,2,3,4 and are testing different paths through a switch or network connected between the ports using a ping or telnet from one port to another, that ping will not actually go out eth1, it will be looped back internally since it's a single network stack handling all four ports.

Static route entries wouldn't work for this kind of testing, since a ping to eth1 might need to be sent from eth2, eth3, or eth4 depending what part of the external network had to be tested. A static route would restrict eth1-destined traffic to only one eth outgoing interface.

Andy