net.ipv4.ip_forward = 0
eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether 00:1e:67:c5:ed:69 brd ff:ff:ff:ff:ff:ff
    inet 172.16.4.19/24 scope global eth0
int2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether 00:e0:ed:34:3f:ab brd ff:ff:ff:ff:ff:ff
    inet 172.16.4.23/24 scope global int2

int2 не подключен к локальной сети, но почему-то
ping 172.16.4.23 есть и ip neigh show
172.16.4.19 dev eth0 lladdr 00:1e:67:c5:ed:69 STALE
172.16.4.23 dev eth0 lladdr 00:1e:67:c5:ed:69 REACHABLE
или arp -a
? (172.16.4.19) at 00:1e:67:c5:ed:69 [ether] on eth0
? (172.16.4.23) at 00:1e:67:c5:ed:69 [ether] on eth0