hi, 

My system is Ubuntu 13.04, kernel version is 3.8.0-21-generic, bird version is 1.3.10. 

In order to achieve two functions in r0: 

Use ecmp functions to achieve load balancing.

Using iptables connmark modules in solving the problem of address overlap.

I have two devices r0-1, I used the bird's ospf and ecmp function, r0 can learn from r1 to the twodefault route. 

As follows: 

default proto bird 

    nexthop via 192.168.0.1 dev tun1 weight 3 

    nexthop via 192.168.0.2 dev tun2 weight 1 

I use tcpdump, Ethereal found on r0 data is based per_packet forwarded to r1. 

But I'm on r0 configured conntrack. If I use conntrack, so my data from r0 to r1 will generate about connection problems. How do I solve it. 

Whether per_connection function can solve this connection problem? How to open per_connection on ubuntu system? 

Thanks for the help you provided earlier, thanks again ...