[[PageOutline]] = 到達テスト = * [../#networkmap] のネットワークを使用 * などとなっているのはデフォルトゲートウェイを示す * VMを使ったせいか、おかしな挙動が見られたので注意 => [#unexpected] * ~~実機で追試が必要？~~ * iproute2による設定で対応可能 * tcpdumpによるパケットキャプチャ * sudo tcpdump -p -n icmp -i eth? * ex) ubuntu-inner-BB:eth0 => ubuntu-inner-BB上の、「sudo tcpdump -p -n icmp -i eth0」によるパケットキャプチャ = パケットロスするケース = == centos-inner -> ubuntu-outer == * centos-innerのデフォルトゲートウェイの設定により、requestがWANに向かってしまう * centos-innerにstatic routeの設定が必要 * パケット経路 1. centos-inner: -> WAN * centos-inner ~]$ ping 10.0.0.10 -c 1 {{{ PING 10.0.0.10 (10.0.0.10) 56(84) bytes of data. --- 10.0.0.10 ping statistics --- 1 packets transmitted, 0 received, 100% packet loss, time 0ms }}} 1. centos-inner:eth0 {{{ 20:07:51.313947 IP 192.168.50.110 > 10.0.0.10: ICMP echo request, id 44813, seq 1, length 64 }}} == centos-outer -> centos-inner == * centos-outerのデフォルトゲートウェイの設定により、requestがWANに向かってしまう * centos-outerにstatic routeの設定が必要 * パケット経路 1. centos-outer: -> WAN * centos-outer ~]$ ping 10.1.0.110 -c 1 {{{ PING 10.1.0.110 (10.1.0.110) 56(84) bytes of data. --- 10.1.0.110 ping statistics --- 1 packets transmitted, 0 received, 100% packet loss, time 0ms }}} 1. centos-outer:eth0 {{{ 20:17:30.551763 IP 192.168.40.20 > 10.1.0.110: ICMP echo request, id 48141, seq 1, length 64 }}} == inner-BB -> centos-outer == * centos-outerのデフォルトゲートウェイの設定により、replyがWANに向かってしまう * centos-outerにstatic routeの設定が必要 * パケット経路 1. inner-BB: 1. router:eth2 1. router: 1. centos-outer:eth1 1. centos-outer: -> WAN * ubuntu-inner-BB:~$ ping 10.0.0.20 -c 1 {{{ PING 10.0.0.20 (10.0.0.20) 56(84) bytes of data. --- 10.0.0.20 ping statistics --- 1 packets transmitted, 0 received, 100% packet loss, time 0ms }}} 1. ubuntu-inner-BB:eth0 {{{ 18:09:56.550982 IP 10.2.0.10 > 10.0.0.20: ICMP echo request, id 45848, seq 1, length 64 }}} 1. ubuntu-router:eth2 {{{ 18:09:56.719082 IP 10.2.0.10 > 10.0.0.20: ICMP echo request, id 45848, seq 1, length 64 }}} 1. ubuntu-router:eth0 {{{ 18:09:56.719179 IP 10.2.0.10 > 10.0.0.20: ICMP echo request, id 45848, seq 1, length 64 }}} 1. centos-outer:eth1 {{{ 18:09:56.864853 IP 10.2.0.10 > 10.0.0.20: ICMP echo request, id 45848, seq 1, length 64 }}} 1. centos-outer:eth0 {{{ 18:09:56.865503 IP 10.0.0.20 > 10.2.0.10: ICMP echo reply, id 45848, seq 1, length 64 }}} == ubuntu-outer -> centos-inner == * centos-innerのデフォルトゲートウェイの設定により、replyがWANに向かってしまう * centos-innerにstatic routeの設定が必要 * パケット経路 1. ubuntu-outer: 1. router: 1. router:eth1 1. centos-inner:eth1 1. centos-inner: -> WAN * ubuntu-outer:~$ ping 10.1.0.110 -c 1 {{{ PING 10.1.0.110 (10.1.0.110) 56(84) bytes of data. --- 10.1.0.110 ping statistics --- 1 packets transmitted, 0 received, 100% packet loss, time 0ms }}} 1. ubuntu-outer:eth1 {{{ 20:29:41.465087 IP 10.0.0.10 > 10.1.0.110: ICMP echo request, id 31255, seq 1, length 64 }}} 1. ubuntu-router:eth0 {{{ 20:29:41.471692 IP 10.0.0.10 > 10.1.0.110: ICMP echo request, id 31255, seq 1, length 64 }}} 1. ubuntu-router:eth1 {{{ 20:29:41.481482 IP 10.0.0.10 > 10.1.0.110: ICMP echo request, id 31255, seq 1, length 64 }}} 1. centos-inner:eth1 {{{ 20:29:41.437276 IP 10.0.0.10 > 10.1.0.110: ICMP echo request, id 31255, seq 1, length 64 }}} 1. centos-inner:eth0 {{{ 20:29:41.438220 IP 10.1.0.110 > 10.0.0.10: ICMP echo reply, id 31255, seq 1, length 64 }}} = 正常なケース = == ubuntu-inner-BB <=(router)=> ubuntu-outer == * パケット経路 1. inner-BB: 1. router:eth2 1. router: 1. ubuntu-outer: 1. ubuntu-outer: 1. router: 1. router:eth2 1. inner-BB: * ubuntu-inner-BB:~$ ping 10.0.0.10 -c 1 {{{ PING 10.0.0.10 (10.0.0.10) 56(84) bytes of data. 64 bytes from 10.0.0.10: icmp_seq=1 ttl=63 time=10.0 ms --- 10.0.0.10 ping statistics --- 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 10.017/10.017/10.017/0.000 ms }}} 1. ubuntu-inner-BB:eth0 {{{ 18:04:53.003357 IP 10.2.0.10 > 10.0.0.10: ICMP echo request, id 35352, seq 1, length 64 18:04:53.013360 IP 10.0.0.10 > 10.2.0.10: ICMP echo reply, id 35352, seq 1, length 64 }}} 1. ubuntu-router:eth2 {{{ 18:04:53.180070 IP 10.2.0.10 > 10.0.0.10: ICMP echo request, id 35352, seq 1, length 64 18:04:53.180372 IP 10.0.0.10 > 10.2.0.10: ICMP echo reply, id 35352, seq 1, length 64 }}} 1. ubuntu-router:eth0 {{{ 18:04:53.180105 IP 10.2.0.10 > 10.0.0.10: ICMP echo request, id 35352, seq 1, length 64 18:04:53.180366 IP 10.0.0.10 > 10.2.0.10: ICMP echo reply, id 35352, seq 1, length 64 }}} 1. ubuntu-outer:eth1 {{{ 18:04:53.177594 IP 10.2.0.10 > 10.0.0.10: ICMP echo request, id 35352, seq 1, length 64 18:04:53.177684 IP 10.0.0.10 > 10.2.0.10: ICMP echo reply, id 35352, seq 1, length 64 }}} == 違う経路で帰ってくるケース == === ubuntu-outer <=(router)=> ubuntu-inner-AB === * パケット経路 1. ubuntu-outer: 1. router: 1. router:eth1 1. inner-AB:eth0 1. inner-AB: 1. router:eth2 1. router: 1. ubuntu-outer: * ubuntu-outer:~$ ping 10.1.0.30 -c 1 {{{ PING 10.1.0.30 (10.1.0.30) 56(84) bytes of data. 64 bytes from 10.1.0.30: icmp_seq=1 ttl=63 time=36.8 ms --- 10.1.0.30 ping statistics --- 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 36.889/36.889/36.889/0.000 ms }}} 1. ubuntu-outer:eth1 {{{ 20:36:54.692467 IP 10.0.0.10 > 10.1.0.30: ICMP echo request, id 45847, seq 1, length 64 20:36:54.712537 IP 10.1.0.30 > 10.0.0.10: ICMP echo reply, id 45847, seq 1, length 64 }}} 1. ubuntu-router:eth0 {{{ 20:36:54.699054 IP 10.0.0.10 > 10.1.0.30: ICMP echo request, id 45847, seq 1, length 64 20:36:54.718482 IP 10.1.0.30 > 10.0.0.10: ICMP echo reply, id 45847, seq 1, length 64 }}} 1. ubuntu-router:eth1 {{{ 20:36:54.711750 IP 10.0.0.10 > 10.1.0.30: ICMP echo request, id 45847, seq 1, length 64 }}} 1. ubuntu-inner-AB:eth0 {{{ 20:36:54.703190 IP 10.0.0.10 > 10.1.0.30: ICMP echo request, id 45847, seq 1, length 64 }}} 1. ubuntu-inner-AB:eth1 {{{ 20:36:54.706993 IP 10.1.0.30 > 10.0.0.10: ICMP echo reply, id 45847, seq 1, length 64 }}} 1. ubuntu-router:eth2 {{{ 20:36:54.718451 IP 10.1.0.30 > 10.0.0.10: ICMP echo reply, id 45847, seq 1, length 64 }}} == おかしな挙動 == #unexpected * 指定したIPがバインドされたNICを通らずに通信されている * iproute2による対応 => [../iproute#ubuntu-inner-AA] === ubuntu-outer <=(router)=> inner-AA === * inner-AA:eth1 = 10.1.0.20 なので、eth1を通るはずなのにeth0を通っている * ubuntu-outer:~$ ping 10.1.0.20 -c 1 {{{ PING 10.1.0.20 (10.1.0.20) 56(84) bytes of data. 64 bytes from 10.1.0.20: icmp_seq=1 ttl=63 time=25.5 ms --- 10.1.0.20 ping statistics --- 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 25.532/25.532/25.532/0.000 ms }}} 1. ubuntu-outer:eth1 {{{ 20:14:02.893113 IP 10.0.0.10 > 10.1.0.20: ICMP echo request, id 60438, seq 1, length 64 20:14:02.914912 IP 10.1.0.20 > 10.0.0.10: ICMP echo reply, id 60438, seq 1, length 64 }}} 1. ubuntu-router:eth0 {{{ 20:14:02.900364 IP 10.0.0.10 > 10.1.0.20: ICMP echo request, id 60438, seq 1, length 64 20:14:02.920840 IP 10.1.0.20 > 10.0.0.10: ICMP echo reply, id 60438, seq 1, length 64 }}} 1. ubuntu-router:eth1 {{{ 20:14:02.900768 IP 10.0.0.10 > 10.1.0.20: ICMP echo request, id 60438, seq 1, length 64 20:14:02.920824 IP 10.1.0.20 > 10.0.0.10: ICMP echo reply, id 60438, seq 1, length 64 }}} 1. ubuntu-inner-AA:eth0 {{{ 20:14:02.888999 IP 10.0.0.10 > 10.1.0.20: ICMP echo request, id 60438, seq 1, length 64 20:14:02.906825 IP 10.1.0.20 > 10.0.0.10: ICMP echo reply, id 60438, seq 1, length 64 }}} === ubuntu-outer <=(router)=> inner-BB === * inner-BB:eth1 = 10.2.0.20 なので、eth1を通るはずなのにeth0を通っている * ubuntu-outer:~$ ping 10.2.0.20 -c 1 {{{ PING 10.2.0.20 (10.2.0.20) 56(84) bytes of data. 64 bytes from 10.2.0.20: icmp_seq=1 ttl=63 time=26.0 ms --- 10.2.0.20 ping statistics --- 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 26.001/26.001/26.001/0.000 ms }}} 1. ubuntu-outer:eth1 {{{ 21:46:14.403188 IP 10.0.0.10 > 10.2.0.20: ICMP echo request, id 57113, seq 1, length 64 21:46:14.419804 IP 10.2.0.20 > 10.0.0.10: ICMP echo reply, id 57113, seq 1, length 64 }}} 1. ubuntu-router:eth0 {{{ 21:46:14.409977 IP 10.0.0.10 > 10.2.0.20: ICMP echo request, id 57113, seq 1, length 64 21:46:14.424457 IP 10.2.0.20 > 10.0.0.10: ICMP echo reply, id 57113, seq 1, length 64 }}} 1. ubuntu-router:eth2 {{{ 21:46:14.423153 IP 10.0.0.10 > 10.2.0.20: ICMP echo request, id 57113, seq 1, length 64 21:46:14.424369 IP 10.2.0.20 > 10.0.0.10: ICMP echo reply, id 57113, seq 1, length 64 }}} 1. ubuntu-inner-BB:eth0 {{{ 21:46:14.417399 IP 10.0.0.10 > 10.2.0.20: ICMP echo request, id 57113, seq 1, length 64 21:46:14.434352 IP 10.2.0.20 > 10.0.0.10: ICMP echo reply, id 57113, seq 1, length 64 }}} ==== (仮想NICからケーブルを)物理的に切断してみる ==== * VMのNICから(仮想的に)LANケーブルを切断する * ubuntu-outer:~$ ping 10.2.0.20 {{{ PING 10.2.0.20 (10.2.0.20) 56(84) bytes of data. (snip) 64 bytes from 10.2.0.20: icmp_seq=18 ttl=63 time=2.41 ms 64 bytes from 10.2.0.20: icmp_seq=19 ttl=63 time=4.53 ms 64 bytes from 10.2.0.20: icmp_seq=20 ttl=63 time=1.42 ms 64 bytes from 10.2.0.20: icmp_seq=21 ttl=63 time=2.76 ms 64 bytes from 10.2.0.20: icmp_seq=33 ttl=63 time=1.07 ms 64 bytes from 10.2.0.20: icmp_seq=34 ttl=63 time=1.21 ms --- 10.2.0.20 ping statistics --- 34 packets transmitted, 23 received, 32% packet loss, time 33009ms rtt min/avg/max/mdev = 0.635/2.304/4.539/0.935 ms }}} 1. 途中、eth1を切断してもpingは通り続けた 1. eth0を切断するとpacket lost 1. ubuntu-inner-BB:eth0 {{{ 22:07:09.562788 IP 10.2.0.20 > 10.0.0.10: ICMP echo reply, id 38682, seq 18, length 64 22:07:10.574025 IP 10.0.0.10 > 10.2.0.20: ICMP echo request, id 38682, seq 19, length 64 22:07:10.574061 IP 10.2.0.20 > 10.0.0.10: ICMP echo reply, id 38682, seq 19, length 64 22:07:11.571686 IP 10.0.0.10 > 10.2.0.20: ICMP echo request, id 38682, seq 20, length 64 22:07:11.571709 IP 10.2.0.20 > 10.0.0.10: ICMP echo reply, id 38682, seq 20, length 64 22:07:12.572202 IP 10.0.0.10 > 10.2.0.20: ICMP echo request, id 38682, seq 21, length 64 22:07:12.572225 IP 10.2.0.20 > 10.0.0.10: ICMP echo reply, id 38682, seq 21, length 64 22:07:24.572056 IP 10.0.0.10 > 10.2.0.20: ICMP echo request, id 38682, seq 33, length 64 22:07:24.572299 IP 10.2.0.20 > 10.0.0.10: ICMP echo reply, id 38682, seq 33, length 64 22:07:25.572061 IP 10.0.0.10 > 10.2.0.20: ICMP echo request, id 38682, seq 34, length 64 22:07:25.572149 IP 10.2.0.20 > 10.0.0.10: ICMP echo reply, id 38682, seq 34, length 64 }}} * eth1をダウンさせても変わらず 1. ubuntu-inner-BB:eth1 {{{ tcpdump: bind: Network is down }}} 1. ubuntu-inner-BB:~$ ifconfig eth1 {{{ eth1 Link encap:Ethernet HWaddr 00:0c:29:ZZ:ZZ:ZZ inet addr:10.2.0.20 Bcast:10.2.255.255 Mask:255.255.0.0 }}} * 何故かIPがバインドされたまま * VMで同じセグメント(仮想HUB)にNICを繋げているせい？