Re: disable local routing between eth0 and eth1 - iptables

astonishs@xxxxxxxxx wrote:
I've a Linux PC with 2 NICs eth0 and eth1 configured with IP 10.0.0.1
and 20.0.0.1 respectively.

|-------------------|
eth0 (10.0.0.1) ------------| |
| L2 SWITCH |
| |
eth1 (20.0.0.1) ------------| |
|-------------------|

I want to disable local routing between eth0 and eth1 so that whenever
I ping 20.0.0.1 from PC console, ICMP packets should come out of
interface eth0 and should reach eth1 through connected switch.

Similarly, whenever I ping 10.0.0.1 from PC console, ICMP packets
should come out of interface eth1 and should reach eth0 through
connected switch.

How can I do it using iptables, if at all possible?

Thanks in advance.
It will use the switch if you "ping -I eth0 20.0.0.1". Ping alone is using the loopback (127.0.0.1), since the destination is on the same machine.
.

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