One of our customer have following OSPF setup,
Link b/w R1 & R2 is in area 1.
Link b/w R2 & R3 is in area 0.
Link b/w R3 & R4 is in area 1.
and there is a direct link between R1 & R4 as well. Customer wants to disconnect this link so in this case Area 1 will become discontigous. I setup this in a lab environment and found that routes are exchanging between R1 & R4 properly using their respective ABRs i.e R2 & R3 respectively. But routes from each discontigous part of Area 1 are installing as Inter Area routes into routing table of R1 & R4. My question is that what could be the consequences of running OSPF in this type of setup.