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Ospf Virtual-link


I have an Ospf lab and i wish to configure virtual-link so that all routers  can exchange routing tables. I succefully did it for the router 2 in area 1 but  i don't know how i should proceed with router 23 in area 2. Please see the attached topology for more understanding of my lab. thanks.

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Re: Ospf Virtual-link

Hello Lionel,

you don't need a virtual link for each router of area 2 if you have setup a virtual link between router2 and router3 you have provided a point to point logical link to area 0 and this is enough for all routers in area 2, actually it allows area 2 summary routes to reach the backbone area.

To be noted that area 3 in your picture can never be attached to area 0, because a virtual link cannot cross multiple areas to reach area 0.

So if you question is there is a way for area 3 to be part of this OSPF domain the answer is negative.

In real world the use of virtual links is limited to temporary fixes after a network merge and they are quite rare

Hope to help


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