The NBMA network cannot discover neighboring routers through Hello packets. Therefore, you need to manually set the IP address of the neighboring router and specify the election priority to establish the neighbor relationship.
For NBMA networks, if there are no directly reachable links between two routers, you can configure the interface type to P2MP. If the router in NBMA networks has only one peer, you can change the interface type to P2P.
Some special configurations are needed for NBMA networks. Because a router cannot detect neighbor routers by broadcasting hello packets, you must manually configure the IP addresses of its adjacent routers for this interface and their election rights.