How can I give preference to OSPF interarea routes over intra-area routes?
I heard that in OSPF we can give preference to OSPF interarea routes over intra-area if a router has multiple OSPF processes running.
OSPF does a route comparison by the metrics and administrative distances (if they have been changed) for the OSPF processes.
I am aware of a case, when we use OSPF in CE & PE routers in a L3VPN scenario,there we have a facility of extending Intra area domain among PE to PE routers by creating a SHAM links, thereby making a route comparison based on metric.
But here I want to understand this concept through a Scenario [other than L3 VPN]. Can some one please explain this through a topology diagram as to how and where the route comparison actually happens between inter and intra area routes in OSPF [when using multiple processes in single router] ?