auto lo
iface lo inet loopback

auto mgmt1
iface mgmt1 inet6 auto
iface mgmt1 inet dhcp
    pre-up /bin/ip link add mgmt type vrf table mgmt
    pre-up /bin/ip link set up dev mgmt
    pre-up /bin/ip link set master mgmt dev mgmt1
    post-down /bin/ip link del dev mgmt


auto feth1
iface feth1 inet manual
    mtu 9000

auto feth2
iface feth2 inet manual
    mtu 9000


source-directory /etc/network/interfaces.d