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OSPF

26 | Sep

OSPF ProtocolLAB1

• OSPF single area configuration (area 0).

• We need PC0 to make successful ping on PC1.

• Network Topology

Configuration Network Topology

Router Interface Network

R1 Int Gig0/0

Int Gig0/1

192.168.55.2/24

172.16.10.2/24

R2 Int Gig0/0

Int Gig0/1

192.168.44.1/24

192.168.55.1/24

R3 Int Gig0/0

Int Gig0/1

172.16.10.1/24

10.10.22.1/24

Router 1

Router(config)#int gig0/0

Router(config-if)#ip add 192.168.55.2 255.255.255.0

Router(config-if)#no sh

Router(config-if)#int gig0/1

Router(config-if)#ip add 172.16.10.2 255.255.255.0

Router(config-if)#no sh

Router(config-if)#router ospf 1

Router(config-router)#network 192.168.55.0 0.0.0.255 area 0

Router(config-router)#network 172.16.10.0 0.0.0.255 area 0

Router(config-router)#

Router 2

Router(config)#int gig0/0

Router(config-if)#ip add 192.168.44.1 255.255.255.0

Router(config-if)#no sh

Router(config-if)#int gig0/1

Router(config-if)#ip add 192.168.55.1 255.255.255.0

Router(config-if)#no sh

Router(config-if)#router ospf 1

Router(config-router)#network 192.168.44.0 0.0.0.255 area 0

Router(config-router)#network 192.168.55.0 0.0.0.255 area 0

Router(config-router)#

Router(config)#int gig0/0

Router(config-if)#ip add 172.16.10.1 255.255.255.0

Router(config-if)#no sh

Router(config-if)#int gig0/1

Router(config-if)#ip add 10.10.22.1 255.255.255.0

Router(config-if)#no sh

Router(config-if)#router ospf 1

Router(config-router)#network 172.16.10.0 0.0.0.255 area 0

Router(config-router)#network 10.10.22.0 0.0.0.255 area 0

Router(config-router)#

Ping PC0 to PC1

LAB2

• Everything in this lab is already configured except for OSPF.

• It is your goal to configure OSPF and ensure each router can communicate

with each other and you can ping from PCs to other PCs.

• Objectives

✓ Configure OSPF on each router with the process ID of 1.

✓ Set the router id to the loopback address on each router.

✓ Advertise directly connected networks based on subnet.

✓ Advertise loopback through the Lo0 interface (do not use network command).

✓ Verify router connectivity by pinging loopbacks of other routers.

✓ Verify remote network connectivity by pinging between PCs.

• Notes

✓ - R1's loopback should be in Area 0

✓ - R2's loopback should be in Area 1

✓ - R3's loopback should be in Area 2

✓ - R4's loopback should be in Area 3

➢ Bonus: Identify which routers are ABRs, Internals, Backbones, or ASBRs.

• Using passive interface in the end devices.

• Benefits of Passive Interfaces

o Security.

o Resource Optimization.

o Simplified Management.

• Configuration Network Topology.

Router Interface Network Loopback Area

Gig0/0

Gig0/1

Gig0/2

10.0.0.1/8

20.0.0.1/8

30.0.0.1/8

1.1.1.1

Area0

R2 Gig0/0

Gig0/1

10.0.0.2/8

172.16.1.1/24

2.2.2.2 Area0

Area1

R3 Gig0/0

Gig0/1

20.0.0.2/8

172.16.2.1/24

3.3.3.3 Area0

Area2

R4 Gig0/0

Gig0/1

30.0.0.2/8

172.16.3.1/24

4.4.4.4 Area0

Area3

Router 1

Router(config)#int gig0/0

Router(config-if)#ip add 10.0.0.1 255.0.0.0

Router(config-if)#no shutdown

Router(config-if)#int gig0/1

Router(config-if)#ip add 20.0.0.1 255.0.0.0

Router(config-if)#no shutdown

Router(config-if)#int gig0/2

Router(config-if)#ip add 30.0.0.1 255.0.0.0

Router(config-if)#no shutdown

Router(config-if)#int loopback 1

Router(config-if)#ip add 1.1.1.1 255.0.0.0

Router(config)#router ospf 1

Router(config-router)#network 10.0.0.0 0.255.255.255 area 0

Router(config-router)#network 20.0.0.0 0.255.255.255 area 0

Router(config-router)#network 30.0.0.0 0.255.255.255 area 0

Router(config-router)#

Router2

Router(config)#int gig0/0

Router(config-if)#ip add 10.0.0.2 255.0.0.0

Router(config-if)#no shutdown

Router(config-if)#int gig0/1

Router(config-if)#ip add 172.16.1.1 255.255.255.0

Router(config-if)#no shutdown

Router(config-if)#int loopback 1

Router(config-if)#ip add 2.2.2.2 255.0.0.0

Router(config)#router ospf 1

Router(config-router)#network 10.0.0.0 0.255.255.255 area 0

Router(config-router)#network 172.16.1.0 0.0.0.255 area 1

Router(config-router)#passive-interface gig0/1

Router(config-router)#

Router3

Router(config)#

Router(config)#int gig0/0

Router(config-if)#ip add 20.0.0.2 255.0.0.0

Router(config-if)#no shutdown

Router(config-if)#int gig0/1

Router(config-if)#ip add 172.16.2.1 255.255.255.0

Router(config-if)#no shutdown

Router(config-if)#int loopback 1

Router(config-if)#ip add 3.3.3.3 255.0.0.0

Router(config)#router ospf 1

Router(config-router)#network 20.0.0.0 0.255.255.255 area 0

Router(config-router)#network 172.16.2.0 0.0.0.255 area 2

Router(config-router)#passive-interface gig0/1

Router(config-router)#

Router4

Router(config)#

Router(config)#int gig0/0

Router(config-if)#ip add 30.0.0.2 255.0.0.0

Router(config-if)#no shutdown

Router(config-if)#int gig0/1

Router(config-if)#ip add 172.16.3.1 255.255.255.0

Router(config-if)#no shutdown

Router(config-if)#int loopback 1

Router(config-if)#ip add 4.4.4.4 255.0.0.0

Router(config)#router ospf 1

Router(config-router)#network 30.0.0.0 0.255.255.255 area 0

Router(config-router)#network 172.16.3.0 0.0.0.255 area 3

Router(config-router)#passive-interface gig0/1

Router(config-router)#