[...]
allow-hotplug enp0s3
iface enp0s3 inet static
        address 192.168.6.1
        netmask 255.255.255.0
allow-hotplug enp0s8
iface enp0s8 inet static
        address 192.168.7.1
        netmask 255.255.255.0
# külső interfész:
allow-hotplug enp0s9
iface enp0s9 inet static
        address 192.168.5.88
        netmask 255.255.255.0
        gateway 192.168.5.1