root@OpenWrt1:~# traceroute 172.16.0.3
traceroute to 172.16.0.3 (172.16.0.3), 30 hops max, 38 byte packets
1 10.0.0.2 (10.0.0.2) 0.356 ms 0.005 ms 0.200 ms
2 10.0.0.2 (10.0.0.2) 0.288 ms 0.003 ms 0.263 ms
root@OpenWrt1:~#root@OpenWrt1:~# tcpdump -D
1.eth0
2.eth1
3.any (Pseudo-device that captures on all interfaces)
4.lo
root@OpenWrt1:~#root@OpenWrt1:~# tcpdump -i 2 -n not net 192.168.10.0/24 and not net 127.0.0.0/24 and not arp
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth1, link-type EN10MB (Ethernet), capture size 65535 bytes
17:04:50.943145 IP 10.0.0.1.48370 > 172.16.0.3.33435: UDP, length 10
17:04:50.943550 IP 10.0.0.2 > 10.0.0.1: ICMP time exceeded in-transit, length 46
17:04:50.944016 IP 10.0.0.1.48370 > 172.16.0.3.33436: UDP, length 10
17:04:50.944309 IP 10.0.0.2 > 10.0.0.1: ICMP time exceeded in-transit, length 46
17:04:50.944643 IP 10.0.0.1.48370 > 172.16.0.3.33437: UDP, length 10
17:04:50.944939 IP 10.0.0.2 > 10.0.0.1: ICMP time exceeded in-transit, length 46
17:04:50.945309 IP 10.0.0.1.48370 > 172.16.0.3.33438: UDP, length 10
17:04:50.945608 IP 10.0.0.2 > 10.0.0.1: ICMP 172.16.0.3 udp port 33438 unreachable, length 46
17:04:50.946004 IP 10.0.0.1.48370 > 172.16.0.3.33439: UDP, length 10
17:04:50.946309 IP 10.0.0.2 > 10.0.0.1: ICMP 172.16.0.3 udp port 33439 unreachable, length 46
17:04:50.946637 IP 10.0.0.1.48370 > 172.16.0.3.33440: UDP, length 10
17:04:50.946949 IP 10.0.0.2 > 10.0.0.1: ICMP 172.16.0.3 udp port 33440 unreachable, length 46
^C
12 packets captured
12 packets received by filter
0 packets dropped by kernel
root@OpenWrt1:~#root@OpenWrt-2:~# tcpdump -D
1.eth0
2.eth1
3.eth2
4.any (Pseudo-device that captures on all interfaces)
5.lo
root@OpenWrt-2:~#root@OpenWrt-2:~# tcpdump -i 2 -n not net 192.168.10.0/24 and not net 127.0.0.0/24 and not arp
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth1, link-type EN10MB (Ethernet), capture size 65535 bytes
17:04:50.942686 IP 10.0.0.1.48370 > 172.16.0.3.33435: UDP, length 10
17:04:50.942724 IP 10.0.0.2 > 10.0.0.1: ICMP time exceeded in-transit, length 46
17:04:50.943494 IP 10.0.0.1.48370 > 172.16.0.3.33436: UDP, length 10
17:04:50.943514 IP 10.0.0.2 > 10.0.0.1: ICMP time exceeded in-transit, length 46
17:04:50.944131 IP 10.0.0.1.48370 > 172.16.0.3.33437: UDP, length 10
17:04:50.944147 IP 10.0.0.2 > 10.0.0.1: ICMP time exceeded in-transit, length 46
17:04:50.944804 IP 10.0.0.1.48370 > 172.16.0.3.33438: UDP, length 10
17:04:50.944823 IP 10.0.0.2 > 10.0.0.1: ICMP 172.16.0.3 udp port 33438 unreachable, length 46
17:04:50.945495 IP 10.0.0.1.48370 > 172.16.0.3.33439: UDP, length 10
17:04:50.945514 IP 10.0.0.2 > 10.0.0.1: ICMP 172.16.0.3 udp port 33439 unreachable, length 46
17:04:50.946125 IP 10.0.0.1.48370 > 172.16.0.3.33440: UDP, length 10
17:04:50.946153 IP 10.0.0.2 > 10.0.0.1: ICMP 172.16.0.3 udp port 33440 unreachable, length 46
^C
12 packets captured
12 packets received by filter
0 packets dropped by kernel
root@OpenWrt-2:~#root@OpenWrt-2:~# tcpdump -i 3 -n not net 192.168.10.0/24 and not net 127.0.0.0/24 and not arp
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth2, link-type EN10MB (Ethernet), capture size 65535 bytes
^C
0 packets captured
0 packets received by filter
0 packets dropped by kernel
root@OpenWrt-2:~#root@OpenWrt3:~# tcpdump -D
1.eth0
2.eth1
3.any (Pseudo-device that captures on all interfaces)
4.lo
root@OpenWrt3:~#root@OpenWrt3:~# tcpdump -i 2 -n not net 192.168.10.0/24 and not net 127.0.0.0/24 and n
ot arp
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth1, link-type EN10MB (Ethernet), capture size 65535 bytes
^C
0 packets captured
0 packets received by filter
0 packets dropped by kernel
root@OpenWrt3:~#
DISCUSSION