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Module - 2 Single Area OSPF Config

2026-08-20 17:09

Tags: #enterpriseNetwork

Author: Duke Hsu

ospfv2-practice.png

Laboratory Exercise 1 Configuring OSPFv2 in a Single Area

Addressing Table
Device Interface IP Address Subnet Mask Default Gateway
R1 G0/0 172.16.10.1 255.255.255.0
S0/0/0 172.16.1.1 255.255.255.252
S0/0/1 172.16.1.9 255.255.255.252
R2 G0/0 172.16.12.1 255.255.255.0
S0/0/0 172.16.1.2 255.255.255.252
S0/0/1 172.16.20.2 255.255.255.252
R3 G0/0 172.16.11.1 255.255.255.0 N/A
S0/0/0 172.16.1.41 255.255.255.252 N/A
S0/0/1 172.16.1.10 255.255.255.252 N/A
R4 G0/0 172.16.13.1 255.255.255.0 N/A
S0/0/0 172.16.1.42 255.255.255.252 N/A
S0/0/1 172.16.1.21 255.255.255.252 N/A

Objectives

Part 1: Configure OSPFv2 Routing

Part 2: Verify the Configurations

Background

In this activity, the IP addressing is already configured. You are responsible for configuring the three router topology with basic single area OSPFv2 and then verifying connectivity between end devices.

Part 1:     Configure OSPFv2 Routing

Step 1:     Configure OSPF on the R1, R2 , R3 and R4

Use the following requirements to configure OSPF routing on all three routers:

-       Process ID 100 -       Router ID for each router: R1 = 1.1.1.1; R2 = 2.2.2.2; R3 = 3.3.3.3 ; R4 = 4.4.4.4 -       Network address for each interface -       LAN interface set to passive (do not use the default keyword)

Step 2:     Verify OSPF routing is operational.

On each router, the routing table should now have a route to every network in the topology.

Part 2:     Verify the Configurations

Each PC should be able to ping the other two PCs. If not, check your configurations.

OSPF Configuration

R1

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R1(config)#interface loopback 0
    R1(config-if)#ip address 1.1.1.1 255.255.255.255
    R1(config-if)#exit

R1(config)#interface serial 0/0/0
    R1(config-if)#ip address 172.16.1.1 255.255.255.252
    R1(config-if)#no shutdown

R1(config)#interface serial 0/0/1
    R1(config-if)#ip address 172.16.1.9 255.255.255.252
    R1(config-if)#no shutdown

R1#show ip interface brief

R1(config)#router ospf 100
R1(config-router)#passive-interface gigabitEthernet 0/0
    R1(config-router)#network 172.16.1.0 0.0.0.3 area 0
    R1(config-router)#network 172.16.1.8 0.0.0.3 area 0

R1#show ip protocols

R2

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R1(config)#interface loopback 0
    R1(config-if)#ip address 2.2.2.2 255.255.255.255
    R1(config-if)#exit


R2(config)#interface serial 0/0/0
    R1(config-if)#ip address 172.16.1.2 255.255.255.252
    R1(config-if)#no shutdown

R2(config)#interface serial 0/0/1
    R1(config-if)#ip address 172.16.1.22 255.255.255.252
    R1(config-if)#no shutdown

R2#show ip interface brief

R2(config)#router ospf 100
R2(config-router)#passive-interface gigabitEthernet 0/0
    R1(config-router)#network 172.16.1.0 0.0.0.3 area 0
    R1(config-router)#network 172.16.1.20 0.0.0.3 area 0

R2#show ip protocols

R3

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R1(config)#interface loopback 0
    R1(config-if)#ip address 3.3.3.3 255.255.255.255
    R1(config-if)#exit


R2(config)#interface serial 0/0/0
    R1(config-if)#ip address 172.16.1.41 255.255.255.252
    R1(config-if)#no shutdown

R2(config)#interface serial 0/0/1
    R1(config-if)#ip address 172.16.1.10 255.255.255.252
    R1(config-if)#no shutdown

R2#show ip interface brief

R2(config)#router ospf 100
R2(config-router)#passive-interface gigabitEthernet 0/0
    R1(config-router)#network 172.16.1.8 0.0.0.3 area 0
    R1(config-router)#network 172.16.1.40 0.0.0.3 area 0

R2#show ip protocols

R4

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R1(config)#interface loopback 0
    R1(config-if)#ip address 4.4.4.4 255.255.255.255
    R1(config-if)#exit


R2(config)#interface serial 0/0/0
    R1(config-if)#ip address 172.16.1.42 255.255.255.252
    R1(config-if)#no shutdown

R2(config)#interface serial 0/0/1
    R1(config-if)#ip address 172.16.1.21 255.255.255.252
    R1(config-if)#no shutdown

R2#show ip interface brief

R2(config)#router ospf 100
R2(config-router)#passive-interface gigabitEthernet 0/0
    R1(config-router)#network 172.16.1.40 0.0.0.3 area 0
    R1(config-router)#network 172.16.1.20 0.0.0.3 area 0

R2#show ip protocols

DHCP Configuration

R1

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R2(config)#interface gigabitEthernet 0/0
    R2(config-if)#ip address 172.16.10.1 255.255.255.0
    R2(config-if)#no shutdown
    R2(config-if)#exit


R1(config)#ip dhcp excluded-address 172.16.10.1 172.16.10.100

R1(config)#ip dhcp pool LAN10
    R1(dhcp-config)#network 172.16.10.0 255.255.255.0
    R1(dhcp-config)#default-router 172.16.10.1
    R1(dhcp-config)#domain-name dukehsu.com
    R1(dhcp-config)#dns-server 8.8.8.8
    R1(dhcp-config)#end

R1#show ip dhcp pool
R1#show ip dhcp binding


R1#config t
R1(config)#router ospf 100
    R1(config-router)#network 172.16.10.0 0.0.0.255 area 0
    R1(config-router)#end

R1#show ip protocols

R2

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R2(config)#interface gigabitEthernet 0/0
    R2(config-if)#ip address 172.16.12.1 255.255.255.0
    R2(config-if)#no shutdown
    R2(config-if)#exit


R1(config)#ip dhcp excluded-address 172.16.12.1 172.16.12.100

R1(config)#ip dhcp pool LAN10
    R1(dhcp-config)#network 172.16.12.0 255.255.255.0
    R1(dhcp-config)#default-router 172.16.12.1
    R1(dhcp-config)#domain-name dukehsu.com
    R1(dhcp-config)#dns-server 8.8.8.8
    R1(dhcp-config)#end

R1#show ip dhcp pool
R1#show ip dhcp binding


R1#config t
R1(config)#router ospf 100
    R1(config-router)#network 172.16.12.0 0.0.0.255 area 0
    R1(config-router)#end

R1#show ip protocols

R3

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R2(config)#interface gigabitEthernet 0/0
    R2(config-if)#ip address 172.16.11.1 255.255.255.0
    R2(config-if)#no shutdown
    R2(config-if)#exit


R1(config)#ip dhcp excluded-address 172.16.11.1 172.16.12.100

R1(config)#ip dhcp pool LAN10
    R1(dhcp-config)#network 172.16.11.0 255.255.255.0
    R1(dhcp-config)#default-router 172.16.11.1
    R1(dhcp-config)#domain-name dukehsu.com
    R1(dhcp-config)#dns-server 8.8.8.8
    R1(dhcp-config)#end

R1#show ip dhcp pool
R1#show ip dhcp binding


R1#config t
R1(config)#router ospf 100
    R1(config-router)#network 172.16.11.0 0.0.0.255 area 0
    R1(config-router)#end

R1#show ip protocols

R4

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R2(config)#interface gigabitEthernet 0/0
    R2(config-if)#ip address 172.16.13.1 255.255.255.0
    R2(config-if)#no shutdown
    R2(config-if)#exit


R1(config)#ip dhcp excluded-address 172.16.13.1 172.16.12.100

R1(config)#ip dhcp pool LAN10
    R1(dhcp-config)#network 172.16.13.0 255.255.255.0
    R1(dhcp-config)#default-router 172.16.13.1
    R1(dhcp-config)#domain-name dukehsu.com
    R1(dhcp-config)#dns-server 8.8.8.8
    R1(dhcp-config)#end

R1#show ip dhcp pool
R1#show ip dhcp binding


R1#config t
R1(config)#router ospf 100
    R1(config-router)#network 172.16.13.0 0.0.0.255 area 0
    R1(config-router)#end

R1#show ip protocols

Results

OSPF router

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R1#show ip route ospf

172.16.0.0/16 is variably subnetted, 11 subnets, 3 masks

O 172.16.1.20 [110/192] via 172.16.1.10, 00:42:24, Serial0/0/1

O 172.16.1.40 [110/128] via 172.16.1.10, 00:42:24, Serial0/0/1

O 172.16.11.0 [110/65] via 172.16.1.10, 00:11:18, Serial0/0/1

O 172.16.12.0 [110/193] via 172.16.1.10, 00:17:42, Serial0/0/1

O 172.16.13.0 [110/129] via 172.16.1.10, 00:18:36, Serial0/0/1

References

Internet