On Fri, Aug 09, 2002 at 11:00:21PM +0200, Marc Haber wrote: > On Fri, 9 Aug 2002 10:19:36 -0700, Ted Deppner <[EMAIL PROTECTED]> wrote: > >If you want to be able to use both IPs from either network (a common > >occurance even if you didn't plan it), you should probably turn off > >RP_FILTER in the kernel. > > Why?
rp_filter will drop packets coming in interface A that have a source in the network of interface B. It essentially polices that packets that "should" come in B have to come in B. In a well connected mesh, it's possible to have network B devices route packets through to interface A (interface B's cable unplugged, route to B becomes available through A; arp behavior in two NIC networks on the same switch can exhibit this behavior sometimes as well). This is only usually a concern where you have two interfaces facing the same general network traffic. > use tcpdump -e to actually see the MAC addresses where the packets are > sent to. Good point! -- Ted Deppner http://www.psyber.com/~ted/