Taurus

auto eth0
iface eth0 inet static

        address x.x.x.107 
        netmask  255.255.255.0
        network x.x.x.0
        broadcast x.x.x.255
        gateway x.x.x.254

auto vmbr1
iface vmbr1 inet static
        address  y.y.y.119
        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 'y.y.y.119/24' -o vmbr1 -j SNAT --to x.x.x.107

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static
        address {IP_хоста}
        netmask  255.255.255.0
        network 193.70.9.0
        broadcast 193.70.9.255
        gateway 193.70.9.254

auto vmbr0
iface vmbr0 inet static
        address  10.10.10.1
        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 '10.10.10.0/24' -o eth0 -j MASQUERADE