frr defaults traditional
hostname r1
interface eth1
 ip address 10.2.1.1/24
 ip ospf area 0
 ip ospf passive
interface eth2
 ip address 10.2.12.1/24
 ip ospf area 0
 ip ospf hello-interval 1
 ip ospf dead-interval 3
interface eth3
 ip address 10.2.13.1/24
 ip ospf area 0
 ip ospf cost 100
 ip ospf hello-interval 1
 ip ospf dead-interval 3
router ospf
 ospf router-id 10.2.255.1