auto eth0
iface eth0 inet static
address 85.***.**.**
gateway 85.**.**.1
netmask 255.255.255.0
dns-nameservers 8.8.8.8 8.8.4.4
up ip addr add 2a12:*********/64 dev eth0
up ip -6 route add 2a12:*********:0000:0000:0000:0001 dev eth0
up ip -6 route add default via 2a12:****0000:0000:0000:0001