Lab 26 - OSPF Virtual Link Example 3

Prerequisites: CCNP level skills.

Note!
Virtual links are also used to connect dis-contiguous area 0 (e.g. company aquisition etc.)


Topology

Pic. 1 - OSPF Topology.

Icons designed by: Andrzej Szoblik - http://www.newo.pl

Task 1

Configure OSPF so that area 0 is contiguous as per OSPF design requirements. Do not change areas already configured.

Lab Solution

Note!
Before configuring a virtual link, the routing tables are incomplete due to the fact that the backbone area (area 0) is dis-contiguous.

Pic. 2 - R5's Routing Table.

Pic. 3 - R6's Routing Table.

Task 1

Configure OSPF so area 0 is contiguous as per OSPF design requirements. Do not change areas already configured.

R1 Configuration:

!

router ospf 1
 router-id 1.1.1.1
 log-adjacency-changes
 area 1 virtual-link 2.2.2.2
 network 10.1.12.1 0.0.0.0 area 1
 network 10.1.13.1 0.0.0.0 area 0
 network 172.16.101.1 0.0.0.0 area 1

!

R2 Configuration:

!

router ospf 1
 router-id 2.2.2.2
 log-adjacency-changes
 area 1 virtual-link 1.1.1.1
 network 10.1.12.2 0.0.0.0 area 1
 network 10.1.24.2 0.0.0.0 area 0
 network 172.16.102.2 0.0.0.0 area 1

!

Verification:

Pic. 4 - R5's Routing Table.