CCNA3 - Lab 6.3.1 Configuring and Propagating an OSPF Default Route

Step 1: Connect the equipment

Connect each of the routers, switches, and hosts as shown in the topology diagram.

Step 2: Perform basic configurations on the routers

1. Connect a PC to the console port of the router to perform configurations using a terminal emulation program.
2. On Routers 1, 2, and 3, configure the hostname, console, Telnet, privileged passwords, and message-of-the-day banner and disable DNS lookups according to the addressing table and topology diagram.

Step 3: Configure the ISP router

1. Configure serial and loopback interfaces on Router 3.
2. On Router 3, configure a default route to both the 192.168.0.0 and the 192.168.1.0 networks.

Step 4: Configure the Area 0 OSPF routers

1. Configure loopback, FastEthernet, and serial interfaces on Router 1 and Router 2.
2. Save the running configuration to the NVRAM of each router.

 Step 5: Configure the hosts with the proper IP address, subnet mask, and default gateway

Each workstation should be able to ping the attached router. Troubleshoot as necessary. Remember to assign a specific IP address and default gateway to the workstation. At this point, the workstations will not be able to communicate with each other.

Step 6: Verify connectivity

Ping from R2 to both the ISP and R1 routers. Were the pings successful? Jawaban: yes

Step 7: Configure OSPF routing on both Area 0 routers

1. Configure OSPF routing on each router. Use OSPF process number 1 and ensure that all networks are in Area 0.

Step 8: Test network connectivity

Ping the R1 host from the R2 host. Was it successful? Jawaban: yes

Step 9: Observe OSPF traffic

1. At the privileged EXEC mode, enter the command debug ip ospf events and observe the output. You may have to wait at least 40 seconds for the hello packet to be sent before observations can be recorded
2. Turn off debugging by entering no debug ip ospf events or undebug all.

Step 10: Create a default route to the ISP

On R2 only, enter a static default route.

R2(config)#ip route 0.0.0.0 0.0.0.0 200.20.20.1

Step 11: Verify the default static route

Verify the default static route by looking at the R2 routing table.

Step 12: Verify connectivity from the R2 router

1. Verify connectivity from R2 by pinging the ISP Serial 0/0/1 interface from the R2 router.

Is the ping successful? yes

1. Next, on the host attached to R2, open a command prompt and ping the Serial 1 interface on the ISP router.

Is the ping successful? Yes

1. This time, ping the loopback interface address of the ISP router, which represents the ISP connection to the Internet.

Step 13: Verify connectivity from the R1 router.

Verify the connection between the ISP and R1 by pinging the Serial 0/0/1 interface of the ISP router on R2.

Step 14: Redistribute the static default route

Propagate the gateway of last resort to the other routers in the OSPF domain. At the configure router prompt on R2, enter default-information originate.

R2(config-router)#default-information originate

Step 15: Reflection

1. How does OSPF reach networks outside of the domain? Jawaban: OSPF must know about the network or OSPF must have a default route.
2. What does a router use to generate a gateway of last resort? Jawaban: Default route.