Switching

*Note this quesiton has also been posted in the Routing Board*

 

Hi All,

 

I have a setup where I have two fairly large Area 0 networks which need to be interconnected.  The address space is unique between the two.  I see two options in this case

 

A)  Make it one large backbone AREA 0. 

 

B) Create a routing instance on the switch that interconnects the two AREA 0.

 

In point A everything will work fine but I feel that SPF calculation in one AREA 0 does not need to really be flooded out to the other Area.

 

In point B I would need to redistribute all the routes from one instance to the other in order to ensure full redundant route reachablitliy.  This is because the two different areas are interconnected redundantly at two different Points  If I have to do this is there still an advantage to splitting up teh two Areas (Basicly creating to OSPF Autonomous systems)

 

 

I attached a diagram to show how this would be interconnected

 

Thanks All!

I would combine them both into one area. It's cleaner and is less likely to bite you in the hindquarters later. If you do keep them separate, I would design it as if they were truly two separate autonomous systems and use EBGP between them rather than trying to do a hack with VRs. :w

Thanks wtucker.  I will be leaving it as one area.