You define this by yourself through the configuration of your OSPF routing protocol. The subnet X between RtrA and RtrB in your example will reside into area 0 if you configure "network X area 0" on both routers and will be in area 1 if you configure "network X area 1" on both routers. In the first case RtrB will be the ABR; in the second case RtrA will perform this task.
Thanks for your reply, but how is this then extended to the following concept?
NetC -- RtrC ---- RtrB ---- RtrA -- NetA
Again RtrA is in area 0, Rtr B in Area 1, and RtrC in area 2.
From the OSPF Design guide, I think I need a Virtual link transit through area 1, but if I extend Area 0 to the interface on RtrB, I don't need the virtual link any more? In this case Area 1 would also be extended to the link interface on RtrC?
this option would eliminate the need for the virtual link throught area 1, but you cannot assign an interface to 2 areas. Hence, if you extend area 0 to RTR B, you would not be able to use Area 1 anymore. Area2 would connect directly to area 0 on router RtrB.
We have 3 identical switches configured by someone else and would like to claim some of the Gigabit ports(G1/G2/G3/G4) for use on servers. When we try to change the wiring and configuration, we run in to connectivity issues. Attached is a des...
This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
j ai une question j ai achete un routeur cisco 887VA-k9 , je le configuré avec la configuration ci- dessous
si je le lier avec mon pc portable sur l un de ses ports directement ça marche toute est bien ( la connexion internet + m...