OSPF single area configuration Gns3 Lab:

This is tutorial for OSPF(back bone area) configuration on gns3. Connect the router as shown in figure and complete the configuration as under. You can configure the OSPF on Cisco router by two ways:

1.       By network command under the OSPF process

2.       By “ip ospf “commands under the desire interface (support by only new IOS versions)

I have configured R1 & R2 by by method one and other two by “ip ospf” command.

 

R1 config:

R1(config)# interface Serial1/0

R1(config-if)# ip address 172.16.1.1 255.255.0.0

R1(config-if)#no shut

R1(config-if)#exit

R1(config)# router ospf 1

R1(config-router)#Router-id 1.1.1.1

R1(config-router)#network 172.16.0.0 0.0.255.255 area 0

R5 config:

R2(config)# interface Serial1/0

R2(config-if)#  ip address 172.16.1.2 255.255.0.0

R2(config-if)#  no shut

R2(config-if)#  interface FastEthernet2/0

 R2(config-if)#  ip address 10.1.1.1 255.255.255.0

R2(config-if)#  no shut

R2(config)# router ospf 1

R2(config-router)#Router-id 2.2.2.2

R2(config-router)#network 172.16.0.0 0.0.255.255 area 0

R2(config-router)#network 10.1.1.0 0.0.255.255 area 0

R4 config:

R3(config)# interface FastEthernet1/1

R3(config-if)#  ip address 12.1.1.2 255.255.255.0

 R3(config-if)# ip ospf 1 area 0

R3(config-if)#  no shut

R3(config)# interface FastEthernet2/0

 R3(config-if)# ip address 10.1.1.2 255.255.255.0

 R3(config)# ip ospf 1 area 0

R3(config-if)#  no shut

R3(config)# router ospf 1

R3(config-router)# Router-id 3.3.3.3

R3 config:

R4(config)# interface FastEthernet1/0

 R4(config-if)# ip address 12.1.1.1 255.255.255.0

 R4(config-if)# ip ospf 1 area 0

R4(config-if)#  no shut

R4(config)# router ospf 1

R4(config-router)# Router-id 4.4.4.4

Verifications:

1.       Use the ”show ip route” you will find the three OSPF routes on each router.

2.       End to end ping should be successful.