OBJECTIVE:
Let’s check what are the configurations of each of the three routers:
MANILA Router:
MANILA#sh run int s2/0
Building configuration…
Current configuration : 168 bytes
!
interface Serial2/0
ip address 192.168.12.1 255.255.255.0
encapsulation frame-relay
ip ospf network point-to-multipoint non-broadcast
serial restart-delay 0
end
MANILA#sh run int lo0
Building configuration…
Current configuration : 64 bytes
!
interface Loopback0
ip address 10.10.10.1 255.255.255.0
MANILA#sh run | sec ospf
ip ospf network point-to-multipoint non-broadcast
router ospf 1
network 10.10.10.0 0.0.0.255 area 0
network 192.168.12.0 0.0.0.255 area 0
MELBOURNE Router:
MELBOURNE#sh run int s2/0
Building configuration…
Current configuration : 168 bytes
!
interface Serial2/0
ip address 192.168.12.2 255.255.255.0
encapsulation frame-relay
ip ospf network point-to-multipoint non-broadcast
serial restart-delay 0
MELBOURNE#sh run int lo0
Building configuration…
Current configuration : 64 bytes
!
interface Loopback0
ip address 20.20.20.1 255.255.255.0
MELBOURNE#sh run | sec ospf
ip ospf network point-to-multipoint non-broadcast
router ospf 1
network 20.20.20.0 0.0.0.255 area 0
network 192.168.12.0 0.0.0.255 area 0
SINGAPORE Router:
SINGAPORE#sh run int s2/0
Building configuration…
Current configuration : 168 bytes
!
interface Serial2/0
ip address 192.168.12.3 255.255.255.0
encapsulation frame-relay
ip ospf network point-to-multipoint non-broadcast
serial restart-delay 0
SINGAPORE#sh run int lo0
Building configuration…
Current configuration : 64 bytes
!
interface Loopback0
ip address 30.30.30.1 255.255.255.0
end
But as I have checked the “OSPF NEIGHBOR” status on the three routers, I cannot see that it’s already established. It’s has completely no results for the three routers.
MANILA#sh ip ospf neighbor
MELBOURNE#show ip ospf neighbor
SINGAPORE#show ip ospf neighbor
We have to understand here that in order to setup the neighbors or adjacency between the three routers, we have to “MANUALLY ENABLE THE NEIGHBOR”under the OSPF process on MANILA Router as it has both an OSPF interface to both MELBOURNE & SINGAPORE routers.
MANILA(config)#router ospf 1
MANILA(config-router)#neighbor 192.168.12.2
MANILA(config-router)#neighbor 192.168.12.3
The moment, I apply the commands, it goes through a sequence of exchanging HELLO packets until a FULL adjacency were formed.
MANILA#
*Jul 24 09:15:20.555: OSPF-1 PAK : rcv. v:2 t:1 l:48 rid:20.20.20.1 aid:0.0.0.0 chk:B016 aut:0 auk: from Serial2/0
*Jul 24 09:15:20.559: OSPF-1 PAK : rcv. v:2 t:1 l:48 rid:30.30.30.1 aid:0.0.0.0 chk:9C0C aut:0 auk: from Serial2/0
*Jul 24 09:15:20.627: OSPF-1 PAK : rcv. v:2 t:2 l:32 rid:20.20.20.1 aid:0.0.0.0 chk:72CC aut:0 auk: from Serial2/0
*Jul 24 09:15:20.631: OSPF-1 PAK : rcv. v:2 t:1 l:48 rid:20.20.20.1 aid:0.0.0.0 chk:B016 aut:0 auk: from Serial2/0
*Jul 24 09:15:20.671: OSPF-1 PAK : rcv. v:2 t:2 l:32 rid:30.30.30.1 aid:0.0.0.0 chk:56AE aut:0 auk: from Serial2/0
*Jul 24 09:15:20.711: OSPF-1 PAK : rcv. v:2 t:2 l:52 rid:20.20.20.1 aid:0.0.0.0 chk:536B aut:0 auk: from Serial2/0
*Jul 24 09:15:20.775: OSPF-1 PAK : rcv. v:2 t:4 l:76 rid:20.20.20.1 aid:0.0.0.0 chk:BB83 aut:0 auk: from Serial2/0
*Jul 24 09:15:20.779: OSPF-1 PAK : rcv. v:2 t:1 l:48 rid:30.30.30.1 aid:0.0.0.0 chk:9C0C aut:0 auk: from Serial2/0
*Jul 24 09:15:20.783: OSPF-1 PAK : rcv. v:2 t:3 l:36 rid:20.
MANILA#20.20.1 aid:0.0.0.0 chk:ADAC aut:0 auk: from Serial2/0
*Jul 24 09:15:20.787: %OSPF-5-ADJCHG: Process 1, Nbr 20.20.20.1 on Serial2/0 from LOADING to FULL, Loading Done
*Jul 24 09:15:20.867: OSPF-1 PAK : rcv. v:2 t:5 l:44 rid:20.20.20.1 aid:0.0.0.0 chk:B665 aut:0 auk: from Serial2/0
*Jul 24 09:15:20.871: OSPF-1 PAK : rcv. v:2 t:2 l:52 rid:30.30.30.1 aid:0.0.0.0 chk:5E70 aut:0 auk: from Serial2/0
*Jul 24 09:15:20.987: OSPF-1 PAK : rcv. v:2 t:4 l:76 rid:30.30.30.1 aid:0.0.0.0 chk:BA91 aut:0 auk: from Serial2/0
*Jul 24 09:15:20.991: OSPF-1 PAK : rcv. v:2 t:3 l:36 rid:30.30.30.1 aid:0.0.0.0 chk:99A2 aut:0 auk: from Serial2/0
*Jul 24 09:15:20.995: %OSPF-5-ADJCHG: Process 1, Nbr 30.30.30.1 on Serial2/0 from LOADING to FULL, Loading Done
Now, let’s check the “OSPF NEIGHBOR” status of the three routers,
MANILA#show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
30.30.30.1 0 FULL/ – 00:01:42 192.168.12.3 Serial2/0
20.20.20.1 0 FULL/ – 00:01:42 192.168.12.2 Serial2/0
MANILA#
MELBOURNE#show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.10.10.1 0 FULL/ – 00:01:51 192.168.12.1 Serial2/0
MELBOURNE#
SINGAPORE#show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.10.10.1 0 FULL/ – 00:01:43 192.168.12.1 Serial2/0
SINGAPORE#
I can also verify the OSPF NETWORK type using the Command “ip ospf interface
MANILA#show ip ospf interface s2/0
Serial2/0 is up, line protocol is up
Internet Address 192.168.12.1/24, Area 0, Attached via Network Statement
Process ID 1, Router ID 10.10.10.1, Network Type POINT_TO_MULTIPOINT, Cost: 64
Topology-MTID Cost Disabled Shutdown Topology Name
0 64 no no Base
Transmit Delay is 1 sec, State POINT_TO_MULTIPOINT
Timer intervals configured, Hello 30, Dead 120, Wait 120, Retransmit 5
oob-resync timeout 120
Hello due in 00:00:17
Supports Link-local Signaling (LLS)
Cisco NSF helper support enabled
IETF NSF helper support enabled
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 4 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 30.30.30.1
Adjacent with neighbor 20.20.20.1
Suppress hello for 0 neighbor(s)
VERIFICATIONS: Now, let’s see what’s inside the ROUTING TABLE of each of the three routers.
MANILA#show ip route ospf
Codes: L – local, C – connected, S – static, R – RIP, M – mobile, B – BGP
D – EIGRP, EX – EIGRP external, O – OSPF, IA – OSPF inter area
N1 – OSPF NSSA external type 1, N2 – OSPF NSSA external type 2
E1 – OSPF external type 1, E2 – OSPF external type 2
i – IS-IS, su – IS-IS summary, L1 – IS-IS level-1, L2 – IS-IS level-2
ia – IS-IS inter area, * – candidate default, U – per-user static route
o – ODR, P – periodic downloaded static route, H – NHRP, l – LISP
+ – replicated route, % – next hop override
Gateway of last resort is not set
20.0.0.0/32 is subnetted, 1 subnets
O 20.20.20.1 [110/65] via 192.168.12.2, 00:27:40, Serial2/0
30.0.0.0/32 is subnetted, 1 subnets
O 30.30.30.1 [110/65] via 192.168.12.3, 00:27:40, Serial2/0
192.168.12.0/24 is variably subnetted, 4 subnets, 2 masks
O 192.168.12.2/32 [110/64] via 192.168.12.2, 00:27:40, Serial2/0
O 192.168.12.3/32 [110/64] via 192.168.12.3, 00:27:40, Serial2/0
MANILA#
MELBOURNE#show ip route ospf
Codes: L – local, C – connected, S – static, R – RIP, M – mobile, B – BGP
D – EIGRP, EX – EIGRP external, O – OSPF, IA – OSPF inter area
N1 – OSPF NSSA external type 1, N2 – OSPF NSSA external type 2
E1 – OSPF external type 1, E2 – OSPF external type 2
i – IS-IS, su – IS-IS summary, L1 – IS-IS level-1, L2 – IS-IS level-2
ia – IS-IS inter area, * – candidate default, U – per-user static route
o – ODR, P – periodic downloaded static route, H – NHRP, l – LISP
+ – replicated route, % – next hop override
Gateway of last resort is not set
10.0.0.0/32 is subnetted, 1 subnets
O 10.10.10.1 [110/65] via 192.168.12.1, 00:27:56, Serial2/0
30.0.0.0/32 is subnetted, 1 subnets
O 30.30.30.1 [110/129] via 192.168.12.1, 00:27:46, Serial2/0
192.168.12.0/24 is variably subnetted, 4 subnets, 2 masks
O 192.168.12.1/32 [110/64] via 192.168.12.1, 00:27:56, Serial2/0
O 192.168.12.3/32 [110/128] via 192.168.12.1, 00:27:46, Serial2/0
MELBOURNE#
SINGAPORE#show ip route ospf
Codes: L – local, C – connected, S – static, R – RIP, M – mobile, B – BGP
D – EIGRP, EX – EIGRP external, O – OSPF, IA – OSPF inter area
N1 – OSPF NSSA external type 1, N2 – OSPF NSSA external type 2
E1 – OSPF external type 1, E2 – OSPF external type 2
i – IS-IS, su – IS-IS summary, L1 – IS-IS level-1, L2 – IS-IS level-2
ia – IS-IS inter area, * – candidate default, U – per-user static route
o – ODR, P – periodic downloaded static route, H – NHRP, l – LISP
+ – replicated route, % – next hop override
Gateway of last resort is not set
10.0.0.0/32 is subnetted, 1 subnets
O 10.10.10.1 [110/65] via 192.168.12.1, 00:28:22, Serial2/0
20.0.0.0/32 is subnetted, 1 subnets
O 20.20.20.1 [110/129] via 192.168.12.1, 00:28:22, Serial2/0
192.168.12.0/24 is variably subnetted, 4 subnets, 2 masks
O 192.168.12.1/32 [110/64] via 192.168.12.1, 00:28:22, Serial2/0
O 192.168.12.2/32 [110/128] via 192.168.12.1, 00:28:22, Serial2/0
SINGAPORE#
From SINGAPORE, I was able to reach MELBOURNE Loopback via MANILA router.
SINGAPORE#ping 20.20.20.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 20.20.20.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 52/72/88 ms
SINGAPORE#
SINGAPORE#traceroute 20.20.20.1
Type escape sequence to abort.
Tracing the route to 20.20.20.1
VRF info: (vrf in name/id, vrf out name/id)
1 192.168.12.1 64 msec 56 msec 56 msec
2 192.168.12.2 84 msec 56 msec 60 msec
SINGAPORE#
NETWORK LESSON 
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