define the superset of the subnets that should be advertised. Notice the route in Albuquerque's
routing table, which indeed shows 10.1.4.0/22, rather than the four individual subnets.
Class A, B, or C network; larger than the network; or exactly matched to a network. For
instance, 192.168.4.0, 192.168.5.0, 192.168.6.0, and 192.168.7.0 could be summarized into
192.168.4.0/22, which represents four consecutive Class C networks. Summarization when the
summarized group is a set of networks is sometimes called supernetting.
On Albuquerque:
Router eigrp 9
Network 172.16.0.0
No auto-summary
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
C 172.16.1.0 is directly connected, Serial0.2
C 172.16.2.0 is directly connected, Ethenet0
C 172.16.3.0 is directly connected, Serial0.1
10.0.0.0/8 is variably subnetted, 5 subnets, 2 masks
D 10.1.11.0/24 [120/1] via 172.16.3.252, 00:00:15, Serial0.1
D 10.1.10.0/24 [120/1] via 172.16.3.252, 00:00:15, Serial0.1
D 10.1.9.0/24 [120/1] via 172.16.3.252, 00:00:15, Serial0.1
D 10.1.8.0/24 [120/1] via 172.16.3.252, 00:00:15, Serial0.1
D 10.1.4.0/22 [90/2185984] via 172.16.1.253, 00:00:58, Serial0.2
Enabled?
Disabled?
configuration