I am running a server on one interface and a client on another. For certain reasons, I need to make sure all the traffic egresses from the box and isn't locally switched inside the Linux networking stack. Is there a way to force the Linux networking stack to always send packets out the wire even when the destination MAC matches another interface on the same machine?
Is IP forwarding enabled? If so then try disabling it and it will stop the kernel routing between the internal interfaces.
for IPV4 this would be
It's not something I've ever tried but I guess the ipv6 equivalent would be