Want to send traffic between two NICs

Hello
I want to send traffic from one to another NIC on the same Linux box
via router. Is there any way to do that. I meant to say, I have bind
two different IPs from different pools on the two NIC cards of the
same machine. Now I want to send traffic from one NIC and it goes
towards the router which sends the traffic back(forward) to the other
NIC. I have tried different options but I failed. Is there any way to
do that. Currently, the traffic doesnt get out of the machine as it
finds the IP address on the local machine so it just loop back it.

Regards
Karim Asif Sattar

Asif <(E-Mail Removed)> wrote:
> I want to send traffic from one to another NIC on the same Linux box
> via router. Is there any way to do that. I meant to say, I have bind
> two different IPs from different pools on the two NIC cards of the
> same machine. Now I want to send traffic from one NIC and it goes
> towards the router which sends the traffic back(forward) to the
> other NIC. I have tried different options but I failed. Is there any
> way to do that. Currently, the traffic doesnt get out of the machine
> as it finds the IP address on the local machine so it just loop back
> it.

I believe there is no way to do that in a standard Linux kernel (nor
in just about any Unix either IIRC).

I seem to recall a Ben Grear (Greer?) had some patches to various
Linux kernels to enable that behaviour, so some web searching might be
in order.

It does beg the question though - why do you want to do this?

rick jones
--
denial, anger, bargaining, depression, acceptance, rebirth...
where do you want to be today?
these opinions are mine, all mine; HP might not want them anyway...
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...

On Jun 6, 10:19 am, Rick Jones <rick.jon...@hp.com> wrote:
> Asif <karima...@gmail.com> wrote:
> > I want to send traffic from one to another NIC on the same Linux box
> > via router. Is there any way to do that. I meant to say, I have bind
> > two different IPs from different pools on the two NIC cards of the
> > same machine. Now I want to send traffic from one NIC and it goes
> > towards the router which sends the traffic back(forward) to the
> > other NIC. I have tried different options but I failed. Is there any
> > way to do that. Currently, the traffic doesnt get out of the machine
> > as it finds the IP address on the local machine so it just loop back
> > it.
>
> I believe there is no way to do that in a standard Linux kernel (nor
> in just about any Unix either IIRC).
>
> I seem to recall a Ben Grear (Greer?) had some patches to various
> Linux kernels to enable that behaviour, so some web searching might be
> in order.
>
> It does beg the question though - why do you want to do this?
>
> rick jones
> --
> denial, anger, bargaining, depression, acceptance, rebirth...
> where do you want to be today?
> these opinions are mine, all mine; HP might not want them anyway...
> feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...

I need that behavior for some experiment, thanks anyway.
Regards

Asif wrote:
> Hello
> I want to send traffic from one to another NIC on the same Linux box
> via router. Is there any way to do that. I meant to say, I have bind
> two different IPs from different pools on the two NIC cards of the
> same machine. Now I want to send traffic from one NIC and it goes
> towards the router which sends the traffic back(forward) to the other
> NIC. I have tried different options but I failed. Is there any way to
> do that. Currently, the traffic doesnt get out of the machine as it
> finds the IP address on the local machine so it just loop back it.
>
> Regards
> Karim Asif Sattar
>

Have you any control over the router? If you try to send packets from
one NIC to the IP address of the other NIC, the packet will remain
internal to the Linux machine - IP addresses belong to the OS, not to
the NIC. But if you have Linux running on the router, then you could
perhaps send out packets to an address on the router, which then DNATs
the packets to the other IP address on the test box and passes them out
again.

Alternatively, you might get somewhere by playing around with virtual
servers of some sort on the test machine.

mvh.,

David