OSPF Virtual Link
CCNP BSCI
Chapter 3: OSPF [ 39 ]
Area 0 Area 0
Area 1
RID:
10.10.10.10
RID:
10.20.20.20
Virtual Link
R1 R3
Area 1 is the transit area for the virtual link. Configure each end of a virtual
link on the ABRs of the transit area with the command area area-number
virtual-link router-id. Each end of the link is identified by its RID. The area
listed in the command is the transit area, not the area being joined by the
link. The configuration for R1 is:
R1(config)#router ospf 1
R1(config-router)#area 1 virtual-link 10.20.20.20
The configuration for R2 is:
R2(config)#router ospf 1
R2(config-router)#area 1 virtual-link 10.10.10.10
Verify that the virtual link is up with the show ip ospf virtual-links
command. Additionally, virtual interfaces are treated as actual interfaces by
the OSPF process, and thus, their status can be verified with the show ip
ospf interface interface-id command.