Hi Guys,
I have two NIC's interfaces on my linux machine(eth1 and eth2).
Each have different IP addresses(10.0.0.1, 10.67.7.1).
These two interfaces are connected together through hub.

Here is the my question?

1) If I 'ping 10.0.0.1', it should go out through network interface eth2 and through hub and enter on eth1 and response also travel through similar direction.

2) If I 'ping 10.67.7.1', it should go out through network interface eth1 and through hub and enter on eth2.

How can setup routing table for this,
I have tried setting up routing and iptables, etc.. nothing helped.

If any one good router/networking guy, you should know this one.

I am doing a project, I want this way to handle this.


Thanks,
Raj

Well it would be possible if you put in a routing metric in the routing table that's lower than the metric on the interface itself it should do that, but I have to point out how dumb this whole scenario seems...

Hi Acid_kewpie,
I am sure, it looks dump...
working on network testing tool to simulate using Linux machine.
I really need this solution.
Let me know, if you have idea on this.
I appreciate your feedback.

Thanks,
Raj

Can you send output of:
route -n

Thanks.

I do have an idea, I already told you.

Hi nimnull22,
Here is the requested info....

# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
10.0.0.1 0.0.0.0 255.255.255.255 UH 0 0 0 ppp0
10.67.7.1 0.0.0.0 255.255.255.255 UH 0 0 0 ppp1
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
0.0.0.0 0.0.0.0 0.0.0.0 U 0 0 0 ppp0


# ifconfig
eth0 Link encap:Ethernet HWaddr 00:22:15:C8:4E:53
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
Interrupt:29

eth1 Link encap:Ethernet HWaddr 00:50:B6:05:30:FB
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:124 errors:0 dropped:0 overruns:0 frame:0
TX packets:130 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:5824 (5.6 Kb) TX bytes:5765 (5.6 Kb)

eth2 Link encap:Ethernet HWaddr 00:50:B6:05:6A:12
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:130 errors:0 dropped:0 overruns:0 frame:0
TX packets:124 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:6116 (5.9 Kb) TX bytes:5022 (4.9 Kb)

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:172 errors:0 dropped:0 overruns:0 frame:0
TX packets:172 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:11040 (10.7 Kb) TX bytes:11040 (10.7 Kb)

ppp0 Link encap:Point-to-Point Protocol
inet addr:10.67.7.1 P-t-P:10.0.0.1 Mask:255.255.255.255
UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1492 Metric:1
RX packets:6 errors:0 dropped:0 overruns:0 frame:0
TX packets:6 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:3
RX bytes:69 (69.0 b) TX bytes:69 (69.0 b)

ppp1 Link encap:Point-to-Point Protocol
inet addr:10.0.0.1 P-t-P:10.67.7.1 Mask:255.255.255.255
UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1492 Metric:1
RX packets:6 errors:0 dropped:0 overruns:0 frame:0
TX packets:6 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:3
RX bytes:69 (69.0 b) TX bytes:69 (69.0 b)

#

Hi Chris,
I am sure, you have idea on this to resolve it.
Could you send some pointers to start on this, if you don't have much time to get solution?


Thanks,
Raj

I already have, set the metrics on a route to that IP with a lower metric than the interface itself.

Hi Chris,

Thanks for immediate reply...
Here is the my default routing table:
# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
10.0.0.1 0.0.0.0 255.255.255.255 UH 0 0 0 ppp0
10.67.7.1 0.0.0.0 255.255.255.255 UH 0 0 0 ppp1
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
0.0.0.0 0.0.0.0 0.0.0.0 U 0 0 0 ppp0

Then I deleted routing table entry for 10.0.0.1 and 10.67.7.1 and added same routing table entry with gateway as other interface ip address(Because it ahs mtric '0', no more I can do lower than that )

ex: route add -net 10.67.7.1 netmask 255.255.255.0 gw 10.0.0.1 maetric 0 dev ppp1
route add -net 10.0.0.1 netmask 255.255.255.0 gw 10.67.7.1 maetric 0 dev ppp0
when I ping 10.0.0.1, it stll does not go out of interface, it loopbacks from IP layer itself.

I can see 'lo' interface Rx/TX bytes increasing..

later I disabled lo interface (ifdown lo), ping is not going any where.

Hope this will clarifies.

Refer my first mail for my setup, it's a tricky setup.


Summary: Basically my aim is, even if I ping my local interface address(10.0.0.1), it should send my packet to out of interface to ethernet cable.

Thanks,
Raj