What is a virtual link in OSPF?
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.
What is the purpose of OSPF virtual links?
Virtual links use RIDs, and they are another reason why we use fixed RIDs when configuring OSPF. Remember that a virtual link is actually an extension of Area 0. Think of the virtual link as the router’s new interface into Area 0. Configure all interface options on the virtual link.
Can a virtual link be used in OSPF?
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.
How to connect two different areas in OSPF?
In our last post, we have configured OSPF in four routers and created two areas according to the given picture. If you have not yet read our last post, click here to read How to configure OSPF. You can connect two different areas in OSPF by connecting it to the Area 0. For this, we need an additional router. In this example, it is Router 5.
How are OSPF networks divided into sub-domains?
An OSPF network can be divided into sub-domains called areas. An area is a logical collection of OSPF networks, routers, and links that have the same area identification. A router within an area must maintain a topological database for the area to which it belongs. The router does not have detailed information about network topology outside
Can a virtual link be used in a non-backbone area?
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.