Hi, I am an experienced libvirt user on Fedora versions from F15 to F17. I have developped scripts to route trafic from outside on multiple interfaces/multiples IPs to multiple VMs, and back to affect each VM the required external IP address. I have servers with more than hundreds external IPs, and up to 4 VMs, each of them route trafic on different external IPs. I have servers with Fedora F17 which work very fine with this. Now libvirt-1.0.5.9 comes to Fedora 19 with many iptables default rules that refrain me to use my scripts. So I put in /etc/libvirt/hooks /qemu the right rules to get trafic to my VMs, but I can't set trafic back to external with the right external IP. The -j SNAT --to-source ot -j MASQUERADE dont work, are ignored, and I dont see any packet through these rules in iptables -tnat -L POSTROUTING. I used tcpdump to trace packet on the physical server on virbr0 interface and on eth0 interface. I see the packets on outgoing route. But, the ougoing packets are presented to the external interface with the internal address 10.0.0.x instead of the address specified in the -j SNAT rule. Am I the only one in this case? Somebody could help? Thanks Patrick