Search for policy routing. Surprisingly, I cannot find anything about it in the RHEL6 docs. You don't say how exactly you tried. It should be sufficient to edit rt_tables (maybe that's a step you missed? The actual number used doesn't matter) and add the route-eth1/rule-eth1 files on every host involved. I.e. no separate route/rule file shold be needed for the default interfaces. > I then also would like to configure each kvm guest of each host such > that their traffic to the private network segment on the opposite host > routes through the x-over cable via br0 whilst everything else goes > out through br1 to the LAN and gateway. ITYM ... x-over cable via br1 ... out through br0 ... ?