auto vmbr1 iface vmbr1 inet static address 100.64.43.1 netmask 255.255.255.0 bridge_ports none bridge_stp off bridge_fd 0 post-up echo 1 > /proc/sys/net/ipv4/ip_forward post-up iptables -t nat -A POSTROUTING -s '100.64.43.0/24' -o eth0 -j MASQUERADE post-down iptables -t nat -D POSTROUTING -s '100.64.43.0/24' -o eth0 -j MASQUERADE