I have to design an OSPF network. The backbone part, area 0, comprise 2 sites linked by a 100 Mbps LAN extension. Both sites has a WAN link to a MPLS/VPN network running BGP: the main site has a 100 Mbps WAN link and the backup site has a 30 Mbps WAN link. On the provider network, both site share the same RD (Route Distinghuisher) and both VRF's configs export & import all networks from both sites. Each site has an Internet access. The main site will receive the default route directly within the area 0 (PIX running OSPF). In the backup site, the default route will be kept within another area (2).
You can look the GIF i attached.
There is a risk, to lost the 100 Mbps LAN extension link, which will cause the area 0 to be split.
Questions:
1- Is both sites will be able to communicate through the MPLS network in case of failed LAN ext which will split area 0?
2- Should I configure both sites with distinct OSPF domain and redistribute both domains over the 100 Mbps LAN ext.
3- What are the other solutions which should I look?
I will appreciate if you can share your thought about the issues you can think of.
Best regards
Ben