ip address 172.21.2.10 255.255.255.0
ip ospf hello-interval 1
ip ospf dead-interval 4
ip ospf network point-to-point
exit
interface te1/0/22
description "R2"
switchport mode trunk
exit
interface vlan 103
ip address 172.20.1.10 255.255.255.0
ip ospf hello-interval 1
ip ospf dead-interval 4
ip ospf network point-to-point
exit
interface te1/0/23
switchport mode trunk
description "R3"
exit
exit
2 Configure R1:
terminal length 0
config
hostname R1
line console
exec-timeout 0
exit
vlan 101,104
exit
ip routing
router ospf
router-id 1.1.1.1
network 172.21.0.0 0.0.255.255 area 0
timers spf 3 5
exit
interface vlan 101
ip address 172.21.1.1 255.255.255.0
routing
ip ospf hello-interval 1
ip ospf dead-interval 4
ip ospf network point-to-point
exit
interface te1/0/21
switchport mode trunk
1015
Configuring OSPF and OSPFv3