An interface can only belong to one area, although different interfaces on a router can belong to different areas, making the router an Area Border Router. Area Border Routers disseminate routing information or routing changes between areas. Figure 15-2 OSPF Area Dialog Box You can access ...
Configuring OSPF Attributes on Different Types of Networks Configuring OSPF Areas In a stub area, an area border router (ABR) does not transmit autonomous system (AS) external routes, reducing route entries on the ABR as well as the amount of routing information to be transmitted. An NSSA is...
This command applies only to ABRs and is used to summarize routes in an area. Using the asbr-summary command, you can configure an AS boundary router (ASBR) to summarize the routes imported by OSPF. In the same process, ABRs in different areas cannot be configured with abr-summary summary...
Configuring a stub area Configuring an NSSA area Configuring a virtual link Configuring OSPF network types Configuration prerequisites Configuring the broadcast network type for an interface Configuring the NBMA network type for an interface Configuring the P2MP network type for an interface Configuring the...
Define a Not-So-Stubby Area Use the OSPF router configurationareaxxnssacommand in order to define an NSSA. For example, in this topology, Area 2 was configured as an NSSA with thearea 2 nssacommand on all routers in the area. This protects Area 2's internal routers from all the AS-ext...
Enter configuration commands, one per line. End with CNTL/Z. Switch(config)#h MSW1 MSW1(config)#int f0/1 MSW1(config-if)#no sw MSW1(config-if)#ip add 192.168.2.254 255.255.255.0 MSW1(config-if)#int f0/2 MSW1(config-if)#no sw ...
Configuring a stub area is optional. Not every area can be configured as a stub area. A stub area is usually a non-backbone area with only one ABR and is located at the AS border. To ensure the reachability of the routes to destinations outside an AS, the ABR in the stub area gener...
I've just replicated your configuration and voila: R1-Hub(config-router)#do show ip ospf int tun1 Tunnel1 is up, line protocol is up Internet Address 10.255.253.10/24, Area 0 Process ID 100, Router ID 10.10.10.10, Network Type POINT_TO_POINT, Cost: 11111 The intense flapping after...
R1 and R3 will not learn routes to each other because both sides are in different process IDs on router R2. The way we would configure this is on R2, we say 'router ospf 2' at global config, and then 'network 10.0.0.0', the wildcard mask, '0.0.0.255 area 0', and then for ...
Support Status of LSAs in Different Types of Areas Table 1-3Support status of LSAs in different types of areas Area Type Router-LSA (Type 1) Network-LSA (Type 2) Network-Summary-LSA (Type 3) ASBR-Summary-LSA (Type 4) AS-External-LSA (Type 5) ...