OSPF between multiple backbone areas possible ?

I’m in a situation with 4 separate networks, each with it’s own subnet and multiple routers running ospf with independent backbone area.
Now the idea is to enable routing accross all networks but I have limited experience with ospf on ros.

A-----B-----C
|------D-----|

How to configure this with ospf in regard that in the beginning each network runs ospf independantly?
Can I somehow exchange routes between multiple backbone areas or do I have to bring all those networks into one backbone ?

Thx

Igor

My understanding of OSPF is that there can only be one backbone for all routers to pass OSPF data to one another.

If you have a non-contiguous network, i.e. segments that are connected via Internet or VPN, then you need to add Virtual Links in order for the OSPF data to correctly traverse the links.

I tried setting up OSPF as I’ve always heard of horror stories with RIP and originally wanted Dynamic WDS connections, but after much hassle with both Dynamic WDS and OSPF I eventually gave up and now have everything running through Static WDS and RIP quite happily.


Regards


Chris Macneill

make your current backbone areas as other areas, and link them in one backbone area.