R1 enable Config t Int loop0 Ip ospf 1 area 0 Int et0/0 Ip ospf 1 area 0 Ip ospf network point-to-point copy run start R2 Enable Config t Int loop0 Ip ospf 1 area 0 Int et0/0 Ip ospf 1 area 0 Ip ospf network point-to-point Int et0/1 Ip ospf 1 area 0 Ip ospf network point-to-point copy run start R3 Enable Config t Int loop0 Ip ospf 1 area 0 Int et0/1 Ip ospf 1 area 0 Ip ospf network point-to-point copy run start Verification:-