Talk:Multiple network interfaces and ARP flux

Goodmorning,

I have a similar problem.

I have following architecture: 2 PC (PC A and PC B). PC A has 2 Ethernet interfaces (A_eth0 and A_eth1). PC B has 2 Ethernet interfaces (B_eth0 and B_eth1).

A_eth0 is connected through a wire with B_eth0 (in the middle there is a Switch: SWT_0) A_eth1 is connected through a wire with B_eth1 (in the middle there is a Switch: SWT_1)

IP addresses used: A_eth0: 192.168.30.1 A_eth1: 192.168.30.2 B_eth0: 192.168.30.3 B_eth1: 192.168.30.4

netmask: 255.255.255.0

SWT_0 and SWT_1 are 2 different switch (in order to realize a physical separation).

Operating system on both machine: LINUX UBUNTU 9.04

Aim of my test: - realize communication between A_eth0 and B_eth0 - realize communication between A_eth1 and B_eth1 - A_eth0 and B_eth1 HAVEN'T TO communicate - A_eth1 and B_eth0 HAVEN'T TO communicate Problem I have: - IF I remove wire connection between A_eth0 and B_eth0 THEN B_eth0 is achieved by PC A (passing through the wrong interface B_eth1) In this case a non-desired communication between A_eth0 and B_eth1 is established. - IF I remove wire connection between A_eth1 and B_eth1 THEN B_eth1 is achieved by PC A (passing through the wrong interface B_eth0) In this case a non-desired communication between A_eth1 and B_eth0 is established.

I have realized following steps on both machines: sysctl -w net.ipv4.conf.all.arp_filter=1 sysctl -w net.ipv4.conf.all.arp_announce=2 sysctl -w net.ipv4.conf.all.arp_ignore=1

/etc/init.d/networking restart

or sysctl -w net.ipv4.conf.all.arp_filter=0 sysctl -w net.ipv4.conf.all.arp_announce=2 sysctl -w net.ipv4.conf.all.arp_ignore=1

/etc/init.d/networking restart

In any cases the problem is not solved.

Thanks for your attention. Regards Paolo