All areas in an Open Shortest Path First (OSPF) autonomous system must be physically connected to the backbone area (Area 0). In some cases, where this is not possible, you can use a virtual link to connect to the backbone through a non-backbone area. You can also use virtual links to connect two parts of a partitioned backbone through a non-backbone area. The area through which you configure the virtual link, known as a transit area, must have full routing information. The transit area cannot be a stub area. This document examines the OSPF database in a virtual link environment. You can read more about virtual links in the OSPF Design Guide.
Cisco recommends that you have knowledge of these topics:
- Configuring OSPF
- OSPF Inter-Area Routing
This document is not restricted to specific software or hardware versions.
The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.
Refer to Cisco Technical Tips Conventions for more information on document conventions.
In this section, you are presented with the information to configure the features described in this document.
This document uses this network setup:
This document uses these configurations:Read more…