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392 Chapter 6: Routing

Notice as highlighted in Example 6-15 that the routing updates include the individual subnets.
Therefore, Albuquerque can see routes to all subnets of network 10 and can route packets to the
correct destinations in Seville and Yosemite. With auto summary enabled, Albuquerque would
think that both Seville and Yosemite had an equal-metric route to network 10.0.0.0; some
packets would be routed incorrectly.

02:49:14: RIP: received v2 update from 172.16.3.252 on Serial0.1
02:49:14: 10.1.11.0/24 -> 0.0.0.0 in 1 hops
02:49:14: 10.1.10.0/24 -> 0.0.0.0 in 1 hops
02:49:14: 10.1.9.0/24 -> 0.0.0.0 in 1 hops
02:49:14: 10.1.8.0/24 -> 0.0.0.0 in 1 hops
02:49:16: RIP: sending v2 update to 224.0.0.9 via Serial0.1 (172.16.3.251)
02:49:16: 172.16.1.0/24 -> 0.0.0.0, metric 1, tag 0
02:49:16: 172.16.2.0/24 -> 0.0.0.0, metric 1, tag 0
02:49:16: 10.0.0.0/8 -> 0.0.0.0, metric 2, tag 0
02:49:16: RIP: sending v2 update to 224.0.0.9 via Serial0.2 (172.16.1.251)
02:49:16: 172.16.2.0/24 -> 0.0.0.0, metric 1, tag 0
02:49:16: 172.16.3.0/24 -> 0.0.0.0, metric 1, tag 0
02:49:16: 10.0.0.0/8 -> 0.0.0.0, metric 2, tag 0
02:49:16: RIP: sending v2 update to 224.0.0.9 via Ethernet 0 (172.16.2.251)
02:49:16: 172.16.1.0/24 -> 0.0.0.0, metric 1, tag 0
02:49:16: 172.16.3.0/24 -> 0.0.0.0, metric 1, tag 0
02:49:16: 10.0.0.0/8 -> 0.0.0.0, metric 2, tag 0
Albuquerque#no debug all
All possible debugging has been turned off
Albuquerque#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default
U - per-user static route, o - ODR

Gateway of last resort is not set

172.16.0.0/24 is subnetted, 3 subnets
C 172.16.1.0 is directly connected, Serial0.2
C 172.16.2.0 is directly connected, Ethernet0
C 172.16.3.0 is directly connected, Serial0.1
10.0.0.0/24 is subnetted, 8 subnets
R 10.1.11.0 [120/1] via 172.16.3.252, 00:00:15, Serial0.1
R 10.1.10.0 [120/1] via 172.16.3.252, 00:00:15, Serial0.1
R 10.1.9.0 [120/1] via 172.16.3.252, 00:00:15, Serial0.1
R 10.1.8.0 [120/1] via 172.16.3.252, 00:00:15, Serial0.1
R 10.1.7.0 [120/1] via 172.16.1.253, 00:00:03, Serial0.2
R 10.1.6.0 [120/1] via 172.16.1.253, 00:00:03, Serial0.2
R 10.1.5.0 [120/1] via 172.16.1.253, 00:00:03, Serial0.2
R 10.1.4.0 [120/1] via 172.16.1.253, 00:00:03, Serial0.2
Albuquerque#

Example 6-15

Albuquerque's Routing Table When Seville is Not Summarizing (Continued)

ch06.fm Page 392 Monday, March 20, 2000 5:11 PM