NIC to NIC communication.
 

First, the technical stuff. I have two computers connected between two NICs with normal network cable. One computer is an x86, the other an iMac (got it for free, whaddya gonna do?). Both are running Gentoo Linux 1.4. The NIC in the x86 computer is a sis900 onboard NIC and the iMac's is a Tulip NIC. Both NICs work (when they're connected to the router directly, they can hit the internet).

Previously, I'd set up networking between my x86 and my Zaurus PDA using the usbnet module, so I figured that getting these two computers to communicate similarly would follow along the same lines.

Anyway, this is what I've done so far, but with no luck:
on the X86:
ifconfig eth1 192.168.2.101 netmask 255.255.255.0 up
route add -host 192.168.2.102 eth1
<note, eth1 here because eth0 is the NE2k PCI NIC that's connected to the router and then to the internet>

on the iMac:
ifconfig eth0 192.168.2.102 netmask 255.255.255.0 up
route add -host 192.168.2.101 eth0
route add default gw 192.168.2.101

Apart from that, I'm lost. The two can't ping each other. The one thing that I have found is the kernel option for "fast switching" that enables NIC to NIC data transfer, but that's only supported by very few NICs (and this shouldn't really require top of the line hardware, should it?).

To boil it all down: How would you get these two computers to talk to each other?

Are you connecting a cable directly between the two computers?

Twisted pair: If you are directly connecting them and if you are not using a crossover cable they are bumping heads, i.e. transmitting on the same pair. Just will not work. You need either a crossover cable or a hub/router/etc.

Coax cable: Be sure to use a terminator on each end of the cable. Some NICs have a dip switch or jumper to terminate with a resistor on the card. Maybe even a software switch. Otherwise you have to manually add a terminator to each end of the cable.

Interesting, I was thinking that if they were twisting it would cause the problem. Fortunately, I have a converter and another cable. Thanks, I'll give it a whirl!