ip forwarding
ipv6 forwarding

int eth-dummy
 ip addr 172.16.4.4/24
 ip addr fd00:400::4/64

int eth-sw
 ip addr 192.168.2.4/24
 ipv6 address fd00:0:2::4/64

int lo
 ip addr 10.4.4.4/32
 ipv6 address 2001:db8::4/128