Single OSPF Configuration

Router 1
======

R1>enable
R1#configure terminal
R1(config)#interface gigabit 0/0
R1(config-if)#ip address 192.168.10.1 255.255.255.0
R1(config-if)#no shutdown

R1(config-if)#interface serial 0/0/0
R1(config-if)#ip address 203.1.1.1 255.255.255.252
R1(config-if)#clock rate 86400
R1(config-if)#no shutdown
R1(config-if)#exit

R1(config)#router ospf 1
R1(config-router)#network 192.168.10.0 0.0.0.255 area 0
R1(config-router)#network 203.1.1.0 0.0.0.255 area 0

Router 2
======

Router>enable
Router#configure terminal
Router(config)#hostname R2
R2(config)#interface gigabit 0/0
R2(config-if)#ip add 192.168.30.1 255.255.255.0
R2(config-if)#no shutdown

R2(config-if)#interface serial 0/0/0
R2(config-if)#ip address 203.1.1.2 255.255.255.252
R2(config-if)#no shutdown

R2(config-if)#interface serial 0/0/1
R2(config-if)#ip address 203.2.2.1 255.255.255.252
R2(config-if)#clock rate 86400
R2(config-if)#no shutdown
R2(config-if)#exit

R2(config)#router ospf 1
R2(config-router)#network 192.168.30.0 0.0.0.255 area 0
R2(config-router)#network 203.1.1.0 0.0.0.255 area 0
R2(config-router)#network 203.2.2.0 0.0.0.255 area 0

Router 3
=======

Router>enable
Router#configure terminal
Router(config)#hostname R3

R3(config)#interface gigabit 0/0
R3(config-if)#ip address 192.168.50.1 255.255.255.0
R3(config-if)#no shutdown

R3(config-if)#interface serial 0/0/0
R3(config-if)#ip address 203.2.2.2 255.255.255.252
R3(config-if)#clock rate 86400
R3(config-if)#no shutdown
R3(config-if)#exit

R3(config)#router ospf 1
R3(config-router)#network 192.168.50.0 0.0.0.255 area 0
R3(config-router)#network 203.2.2.0 0.0.0.255 area 0