Nel seguito di questo sotto-capitolo verranno elencate le tabelle di routing a regime di ciascun router per verificare la consistenza della rete configurata nel corso di questo capitolo.
Router R1.1:
Router R1.2:
raspberrypi# show ip route
Codes: K - kernel route, C - connected, S - static, R - RIP, O - OSPF, I - IS-IS, B - BGP, A - Babel,
> - selected route, * - FIB route
O>* 20.0.0.0/30 [110/20] via 192.168.10.6, s1, 01:24:02 O>* 20.0.0.4/30 [110/30] via 192.168.10.6, s1, 01:24:02 O>* 20.0.0.8/30 [110/30] via 192.168.10.6, s1, 01:24:02 C>* 127.0.0.0/8 is directly connected, lo O>* 137.204.1.0/24 [110/30] via 192.168.10.6, s1, 00:03:14 O 137.204.64.0/24 [110/10] is directly connected, s1, 00:00:17 C>* 137.204.64.0/24 is directly connected, s1, 00:00:17 O 137.204.65.0/24 [110/10] is directly connected, s1, 00:00:17 C>* 137.204.65.0/24 is directly connected, s1, 00:00:17 O 137.204.66.0/24 [110/10] is directly connected, s1, 00:00:17 C>* 137.204.66.0/24 is directly connected, s1, 00:00:17 O 137.204.67.0/24 [110/10] is directly connected, s1, 00:00:17 C>* 137.204.67.0/24 is directly connected, s1, 00:00:17 O>* 137.204.100.0/24 [110/30] via 192.168.10.6, s1, 00:00:14 O>* 137.204.101.0/24 [110/50] via 192.168.10.6, s1, 00:09:32 O>* 192.168.10.0/30 [110/10] is directly connected, s1, 00:00:17 O>* 192.168.10.4/30 [110/10] is directly connected, s1, 00:00:17 O>* 192.168.10.8/30 [110/20] via 192.168.10.6, s1, 00:10:49 O>* 192.168.20.0/29 [110/40] via 192.168.10.6, s1, 00:09:32
raspberrypi# show ip route
Codes: K - kernel route, C - connected, S - static, R - RIP, O - OSPF, I - IS-IS, B - BGP, A - Babel,
> - selected route, * - FIB route
O>* 20.0.0.0/30 [110/20] via 192.168.10.10, s1, 00:01:57 O>* 20.0.0.4/30 [110/30] via 192.168.10.10, s1, 00:01:57 O>* 20.0.0.8/30 [110/30] via 192.168.10.10, s1, 00:01:57 C>* 127.0.0.0/8 is directly connected, lo O 137.204.1.0/24 [110/10] is directly connected, s1, 00:00:17 C>* 137.204.1.0/24 is directly connected, s1 O>* 137.204.64.0/24 [110/30] via 192.168.10.2, s1, 00:01:57 O>* 137.204.65.0/24 [110/30] via 192.168.10.2, s1, 00:01:57 O>* 137.204.66.0/24 [110/10] via 192.168.10.2, s1, 00:01:57 O>* 137.204.67.0/24 [110/10] via 192.168.10.2, s1, 00:01:57 O>* 137.204.100.0/24 [110/30] via 192.168.10.10, s1, 00:00:14 O>* 137.204.101.0/24 [110/50] via 192.168.10.10, s1, 00:09:32 O 192.168.10.0/30 [110/10] is directly connected, s1, 00:03:22 C>* 192.168.10.0/30 is directly connected, s1 O>* 192.168.10.4/30 [110/10] via 192.168.10.10, s1, 00:03:22 O>* 192.168.10.8/30 [110/20] is directly connected, s1, 00:10:49 C>* 192.168.10.8/30 is directly connected, s1
Router R1.3:
Router 0:
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raspberrypi# show ip routeCodes: K - kernel route, C - connected, S - static, R - RIP, O - OSPF, I - IS-IS, B - BGP, A - Babel,
> - selected route, * - FIB route
O 20.0.0.0/30 [110/10] is directly connected, eth0, 00:47:15 C>* 20.0.0.0/30 is directly connected, eth0
O 20.0.0.4/30 [110/10] is directly connected, eth1, 01:44:00 C>* 20.0.0.4/30 is directly connected, eth1
O 20.0.0.8/30 [110/10] is directly connected, eth2, 00:33:09 C>* 20.0.0.8/30 is directly connected, eth2
C>* 127.0.0.0/8 is directly connected, lo
O>* 137.204.64.0/24 [110/30] via 20.0.0.1, eth0, 01:15:42 O>* 137.204.65.0/24 [110/30] via 20.0.0.1, eth0, 01:15:42 O>* 137.204.66.0/24 [110/30] via 20.0.0.1, eth0, 01:15:42 O>* 137.204.67.0/24 [110/30] via 20.0.0.1, eth0, 01:15:42 O>* 137.204.100.0/24 [110/30] via 20.0.0.6, eth1, 00:01:20 O>* 137.204.101.0/24 [110/30] via 20.0.0.6, eth1, 00:01:20 O>* 192.168.10.0/30 [110/30] via 20.0.0.1, eth0, 01:15:42 O>* 192.168.10.4/30 [110/20] via 20.0.0.1, eth0, 01:24:47 O>* 192.168.10.8/30 [110/20] via 20.0.0.1, eth0, 00:02:36 O>* 192.168.20.0/29 [110/20] via 20.0.0.6, eth1, 00:01:20 raspberrypi# show ip route
Codes: K - kernel route, C - connected, S - static, R - RIP, O - OSPF, I - IS-IS, B - BGP, A - Babel,
> - selected route, * - FIB route
O 20.0.0.0/30 [110/10] is directly connected, eth2, 02:39:13 C>* 20.0.0.0/30 is directly connected, eth2
O>* 20.0.0.4/30 [110/20] via 20.0.0.2, eth2, 02:38:31 O>* 20.0.0.8/30 [110/20] via 20.0.0.2, eth2, 02:25:35 C>* 127.0.0.0/8 is directly connected, lo
O>* 137.204.1.0/24 [110/10] via 192.168.10.9, eth1, 01:16:31 O>* 137.204.64.0/24 [110/20] via 192.168.10.5, eth0, 01:16:31 O>* 137.204.65.0/24 [110/20] via 192.168.10.5, eth0, 01:16:31 O>* 137.204.66.0/24 [110/20] via 192.168.10.5, eth0, 01:16:31 O>* 137.204.67.0/24 [110/20] via 192.168.10.5, eth0, 01:16:31 O>* 137.204.100.0/24 [110/30] via 20.0.0.2, eth2, 00:03:14 O>* 137.204.101.0/24 [110/40] via 20.0.0.2, eth2, 00:02:09 O>* 192.168.10.0/30 [110/20] via 192.168.10.5, eth0, 00:22:15 O 192.168.10.4/30 [110/10] via 192.168.10.10, eth0, 00:03:22 C>* 192.168.10.4/30 is directly connected, eth0
O 192.168.10.8/30 [110/10] is directly connected, eth1, 00:03:26 C>* 192.168.10.8/30 is directly connected, eth1
Router R2.1:
Router R2.2:
raspberrypi# show ip route
Codes: K - kernel route, C - connected, S - static, R - RIP, O - OSPF, I - IS-IS, B - BGP, A - Babel,
> - selected route, * - FIB route
O>* 20.0.0.0/30 [110/20] via 20.0.0.5, eth1, 00:15:07
O 20.0.0.4/30 [110/10] is directly connected, eth1, 00:15:57 C>* 20.0.0.4/30 is directly connected, eth1
O>* 20.0.0.8/30 [110/20] via 20.0.0.5, eth1, 00:15:07 C>* 127.0.0.0/8 is directly connected, lo
O>* 137.204.64.0/24 [110/40] via 20.0.0.5, eth1, 00:15:07 O>* 137.204.65.0/24 [110/40] via 20.0.0.5, eth1, 00:15:07 O>* 137.204.66.0/24 [110/40] via 20.0.0.5, eth1, 00:15:07 O>* 137.204.67.0/24 [110/40] via 20.0.0.5, eth1, 00:15:07 O>* 137.204.100.0/24 [110/20] via 192.168.20.2, eth0, 00:05:45 O>* 137.204.101.0/24 [110/20] via 192.168.20.3, eth0, 00:05:45 O>* 192.168.10.0/30 [110/40] via 20.0.0.5, eth0, 00:15:07 O>* 192.168.10.4/30 [110/30] via 20.0.0.5, eth0, 00:15:07 O>* 192.168.10.8/30 [110/40] via 20.0.0.5, eth0, 00:15:07
O 192.168.20.0/29 [110/20] is directly connected, eth0, 00:14:58 C>* 192.168.20.0/29 is directly connected, eth0
raspberrypi# show ip route
Codes: K - kernel route, C - connected, S - static, R - RIP, O - OSPF, I - IS-IS, B - BGP, A - Babel,
> - selected route, * - FIB route
O>* 20.0.0.0/30 [110/20] via 20.0.0.9, s1, 00:02:34 O>* 20.0.0.4/30 [110/20] via 20.0.0.9, s1, 00:02:34 O 20.0.0.8/30 [110/10] is directly connected, s1, 00:03:24 C>* 20.0.0.8/30 is directly connected, s1 C>* 127.0.0.0/8 is directly connected, lo O>* 137.204.64.0/24 [110/40] via 20.0.0.9, s1, 00:02:34 O>* 137.204.65.0/24 [110/40] via 20.0.0.9, s1, 00:02:34 O>* 137.204.66.0/24 [110/40] via 20.0.0.9, s1, 00:02:34 O>* 137.204.67.0/24 [110/40] via 20.0.0.9, s1, 00:02:34 O 137.204.100.0/24 [110/10] is directly connected, s1, 00:03:24 C>* 137.204.100.0/24 is directly connected, s1 O>* 137.204.101.0/24 [110/20] via 192.168.20.3, s1, 00:02:34 O>* 192.168.10.0/30 [110/40] via 20.0.0.9, s1, 00:02:34 O>* 192.168.10.4/30 [110/30] via 20.0.0.9, s1, 00:02:34 O>* 192.168.10.8/30 [110/40] via 20.0.0.9, s1, 00:02:34 O 192.168.20.0/29 [110/10] is directly connected, s1, 00:03:24 C>* 192.168.20.0/29 is directly connected, s1
Router 2.3:
Come si nota dalle tabelle, tutta la rete è conosciuta e raggiungibile da ciascun nodo. Applicando il comando traceroute, che permette di vedere il percorso intrapreso e i router
intercettati dei pacchetti inviati, tra un host virtuale h1 della LAN interna al Router2.3 e uno degli host virtuali presenti nel Router1.1 si ottiene un risultato di questo tipo:
mininet>h1 traceroute -n 137.204.64.1
traceroute to 137.204.64.1 (137.204.64.1) 30 hops max, 60 byte packets 1 137.204.101.254 46.700ms 46.710ms 45.833ms 2 192.168.20.1 51.019ms 52.514ms 51.385ms 3 20.0.0.5 51.506ms 65.532ms 65.087ms 4 20.0.0.1 51.338ms 51.478ms 50.081ms 5 192.168.10.5 67.237ms 54.925ms 90.833ms 7 137.204.64.1 80.348ms 81.543ms 80.798ms
In questa configurazione di rete i pacchetti che partono da h1 (in R2.3) vengono consegnati tramite s1 al router che attraverso lo switch s2 invia i pacchetti all’esterno. Successivamente il pacchetto viene consegnato al router scelto dal protocollo OSPF, in questo caso R2.1 con 192.168.20.1 che, a sua volta, lo consegnerà al router di backbone R0 (20.0.0.5). R0 lo consegna al router di bordo dell’area 1 R1.3 (20.0.0.1) che trasmette il pacchetto all’ultimo router rappresentato da R1.1 che, internamente, consegna il pacchetto alla destinazione h1. Si è dimostrato praticamente che c’è connessione tra LAN1 e LAN7.
Interessante è anche il test del percorso che un pacchetto fa per essere consegnato da una LAN virtuale ad un’altra. Ad esempio, facendo il tra un host della LAN1 e uno della LAN2 si ottiene:
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raspberrypi# show ip routeCodes: K - kernel route, C - connected, S - static, R - RIP, O - OSPF, I - IS-IS, B - BGP, A - Babel,
> - selected route, * - FIB route
O>* 20.0.0.0/30 [110/30] via 192.168.20.1, s2, 00:05:04 O>* 20.0.0.4/30 [110/20] via 192.168.20.1, s2, 00:05:04 O>* 20.0.0.8/30 [110/30] via 192.168.20.1, s2, 00:05:04 C>* 127.0.0.0/8 is directly connected, lo O>* 137.204.64.0/24 [110/50] via 192.168.20.1, s2, 00:05:04 O>* 137.204.65.0/24 [110/50] via 192.168.20.1, s2, 00:05:04 O>* 137.204.66.0/24 [110/50] via 192.168.20.1, s2, 00:05:04 O>* 137.204.67.0/24 [110/50] via 192.168.20.1, s2, 00:05:04 O>* 137.204.100.0/24 [110/10] via 192.168.20.2, s2, 00:05:04 O 137.204.101.0/24 [110/10] is directly connected, s1, 00:11:19 C>* 137.204.101.0/24 is directly connected, s1 O>* 192.168.10.0/30 [110/50] via 192.168.20.1, s2, 00:05:04 O>* 192.168.10.4/30 [110/40] via 192.168.20.1, s2, 00:05:04 O>* 192.168.10.8/30 [110/40] via 192.168.20.1, s2, 00:05:04 O 192.168.20.0/29 [110/10] is directly connected, s2, 00:05:04 C>* 192.168.20.0/29 is directly connected, s2
mininet>h1 traceroute -n h2
traceroute to 137.204.65.1 (137.204.65.1) 30 hops max, 60 byte packets 1 137.204.65.1 16.373ms 24.016ms 14.973ms
Si nota che il pacchetto non incontra nessun router poiché sono entrambi nello stesso dominio di broadcast quindi il pacchetto è come se fosse consegnato in maniera diretta, giungendo subito alla destinazione.
È possibile verificare il percorso intrapreso dai pacchetti che partono dalla rete virtuale Mininet del router R2.1 e giunge nella rete virtuale di R1.1:
mininet>h1 traceroute -n 137.204.64.1
traceroute to 137.204.64.1 (137.204.64.1) 30 hops max, 60 byte packets 1 137.204.100.254 17.798ms 16.379ms 18.799ms
2 20.0.0.5 54.780ms 51.012ms 60.571ms 3 20.0.0.1 63.820ms 62.532ms 57.962ms 4 192.168.10.5 75.950ms 77.002ms 86.176ms 5 137.204.64.1 87.200ms 90.925ms 90.833ms
In questo caso i dati arrivano allo switch (137.204.100.254). Esso li manda al kernel che funge da router e provvede a spedirli verso l’esterno. Il pacchetto arriva quindi al router vicino (20.0.0.5 - R0) e attraverso R1.3 (20.0.0.1) e R1.1 (192.168.10.5) arriva alla rete virtuale di destinazione. Si verifica la connessione anche tra la LAN5 e la LAN1, restando sempre nella stessa area:
mininet>h1 traceroute -n 137.204.64.1
traceroute to 137.204.64.1 (137.204.64.1) 30 hops max, 60 byte packets 1 137.204.1.254 27.148ms 153.822ms 125.661ms
2 192.168.10.1 266.646ms 258.326ms 284.837ms 3 137.204.64.1 287.186ms 288.000ms 288.548ms
Si nota che il pacchetto esce dal nodo R1.2 e arriva al router R1.1 nella porta eth1 (192.168.10.10) e entra nella rete virtuale arrivando a destinazione.