IP Link-State Routing Protocols - CCIE Routing and Switching Exam Certification Guide - page 395

Now, summarize networks 192.16.100.64/29, 192.16.100.72/29, 192.16.100.80/29, and
192.16.100.88/29 by using the OSPF area range command. The networks are summarized
in the ABR for the area Router 9. The configuration change for Router 9 is shown in
Example 8-15.
Example 8-15 Route Summarization using area range
router ospf 100
area 20 range 192.16.100.64 255.255.255.224
The range of addresses 192.16.100.64 255.255.255.224 includes the four new routes. Now ,the
route is summarized and added to Router 3's table, as shown in Example 8-16.
Example 8-16 Routing Table Displaying the Summarized Route
router3#sh 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
O E2 10.0.0.0/8 [110/1000] via 192.16.100.18, 00:27:45, Ethernet0
192.16.100.0/24 is variably subnetted, 11 subnets, 5 masks
O 192.16.100.128/27 [110/74] via 192.16.100.246, 00:48:54, Serial0.1
C 192.16.100.244/30 is directly connected, Serial0.1
O IA 192.16.100.240/30 [110/74] via 192.16.100.18, 00:27:46, Ethernet0
O IA 192.16.100.32/28 [110/84] via 192.16.100.18, 00:27:46, Ethernet0
C 192.16.100.16/28 is directly connected, Ethernet0
C 192.16.100.4/32 is directly connected, Loopback0
O 192.16.100.5/32 [110/65] via 192.16.100.246, 00:48:54, Serial0.1
O 192.16.100.2/32 [110/11] via 192.16.100.18, 00:27:56, Ethernet0
O IA 192.16.100.3/32 [110/75] via 192.16.100.18, 00:27:46, Ethernet0
O IA 192.16.100.64/27 [110/80] via 192.16.100.18, 00:03:13, Ethernet0
Only the summary route is now displayed in the routing table.
Totally Stubby Area Configuration
In this section, you see what happens when you configure area 10 as a totally stubby area.
First, area 10 is configured as a stub area, and the link-state database and routing tables of a
router in the stub area are displayed. Next, area 10 is made a totally stubby area, with the same
tables displayed.