Don't route. Use the ethernet bridge driver and tcpdump. man brctl > -----Original Message----- > From: linux-net-owner@vger.kernel.org > [mailto:linux-net-owner@vger.kernel.org] On Behalf Of Luesley, William > Sent: Tuesday, August 10, 2004 3:01 PM > To: 'linux-net@vger.kernel.org' > Subject: Network routing issue > > > > I have two devices setup as follows: > > > A --------------- B > 192.168.1.1 192.168.1.2 > > > The machines open a number of TCP and UDP ports with which to > communicate. > In order to help testing, I have been asked to place a third > machine between > these two which will be capable of intercepting and modifying > any messages. > My initial plan was to have a device which could mimic both > ends of the > connection (as I already have code to do this); with each > connection being > on a separate NIC, leading to a setup as shown below: > > A ------------ C C ---------- B > 192.168.1.1 192.168.1.2 192.168.1.1 192.168.1.2 > (eth0) (eth1) > > The obvious problem with this is that as C implements both ends of the > interface, any messages it sends are routed internally, > rather than being > sent to the correct host. > > I thought it would be possible to correct this by specifying > the host routes > using the route command, i.e. setting a route to 192.168.1.1 > via device eth0 > and to 192.168.1.2 via eth1, therefore stopping the internal > routing from > occurring. Even with these routes setup, the messages are still routed > internally. > > > > Can the route somehow be forced? > > If not, is there a way to stop the internal routing, > preferably without a > code change to the kernel (if it is a code change - can > someone point me > towards the file)? > > Can I use IP Tables, how? > > Or, am I on totally the wrong track? > > > Thanks for peoples time spent reading and looking into this. > > > > > > > > ******************************************************************** > This email and any attachments are confidential to the intended > recipient and may also be privileged. If you are not the intended > recipient please delete it from your system and notify the sender. > You should not copy it or use it for any purpose nor disclose or > distribute its contents to any other person. > ******************************************************************** > - > : send the line "unsubscribe > linux-net" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
