1pc, 2 network devices in same network -> ping problem

Hello,

Consider the following situation:

kernel 2.4
1 pc, 2 network devices
Both devices have an IP of the same network e.g.
net_device1 has IP 192.168.0.1
net_device2 has IP 192.168.0.2

This results in the following routing table
(dependent of which device is firstly initialized with ifconfig ...
up):
....
....
192.168.0.0 * 255.255.0.0 U 0 0 0 net_device2
192.168.0.0 * 255.255.0.0 U 0 0 0 net_device1

When pinging to net_device1,
net_device2 responds to the arp-request and the ping instead of
net_device1 (even when the cable of net_device1 is unplugged).
Thus net_device2 kind of becomes the "gateway" of network 192.168.0.0.
Net_device1 never responds.

How can I change this behavior to obtain that:
- net_device1 responds to an arp-request and a ping to 192.168.0.1
- net_device2 responds to an arp-request and a ping to 192.168.0.2 ?

This is needed for monitoring purposes (to be able to switch between a
main e.g. net_device1 and backup device e.g. net_device2).

Thx
Pieter Beyens