7.2.1 Packet Tracer – Configure OSPF Advanced Features Answers
Packet Tracer – Configure OSPF Advanced Features (Answers Version)
Answers Note: Red font color or gray highlights indicate text that appears in the instructor copy only.
Addressing Table
Device |
Interface |
IPv4 Address |
Subnet Mask |
Default Gateway |
R1 |
G0/0 |
172.16.1.1 |
255.255.255.0 |
N/A |
R1 |
S0/0/0 |
172.16.3.1 |
255.255.255.252 |
N/A |
R1 |
S0/0/1 |
192.168.10.5 |
255.255.255.252 |
N/A |
R2 |
G0/0 |
172.16.2.1 |
255.255.255.0 |
N/A |
R2 |
S0/0/0 |
172.16.3.2 |
255.255.255.252 |
N/A |
R2 |
S0/0/1 |
192.168.10.9 |
255.255.255.252 |
N/A |
R2 |
S0/1/0 |
209.165.200.225 |
255.255.255.224 |
N/A |
R3 |
G0/0 |
192.168.1.1 |
255.255.255.0 |
N/A |
R3 |
S0/0/0 |
192.168.10.6 |
255.255.255.252 |
N/A |
R3 |
S0/0/1 |
192.168.10.10 |
255.255.255.252 |
N/A |
PC1 |
NIC |
172.16.1.2 |
255.255.255.0 |
172.16.1.1 |
PC2 |
NIC |
172.16.2.2 |
255.255.255.0 |
172.16.2.1 |
PC3 |
NIC |
192.168.1.2 |
255.255.255.0 |
192.168.1.1 |
Objectives
Part 1: Modify OSPF Default Settings
Part 2: Verify Connectivity
Scenario
In this activity, OSPF is already configured and all end devices currently have full connectivity. You will modify the default OSPF routing configurations by changing the hello and dead timers and adjusting the bandwidth of a link. Then you will verify that full connectivity is restored for all end devices.
Instructions
Part 1:Modify OSPF Default Settings
Step 1:Test connectivity between all end devices.
Before modifying the OSPF settings, verify that all PCs can ping the web server and each other.
Step 2:Adjust the hello and dead timers between R1 and R2.
- Enter the following commands on R1.
R1(config)# interface s0/0/0
R1(config-if)# ip ospf hello-interval 15
R1(config-if)# ip ospf dead-interval 60
- After a short period of time, the OSPF connection with R2 will fail. Both sides of the connection need to have the same timers for the adjacency to be maintained. Adjust the timers on R2.
Step 3:Adjust the bandwidth setting on R1.
- Trace the path between PC1 and the web server located at 64.100.1.2. Notice that the path from PC1 to 64.100.1.2 is routed through R2. OSPF prefers the lower cost path.
- On the R1 Serial 0/0/0 interface, set the bandwidth to 64 Kb/s. This does not change the actual port speed, only the metric that the OSPF process on R1 will use to calculate best routes.
R1(config-if)# bandwidth 64
- Trace the path between PC1 and the web server located at 64.100.1.2. Notice that the path from PC1 to 64.100.1.2 is redirected through R3. OSPF prefers the lower cost path.
Part 2:Verify Connectivity
Verify all PCs can ping the web server and each other.
End of document
Answer Scripts
Router R1
interface Serial0/0/0
bandwidth 64
ip ospf hello-interval 15
ip ospf dead-interval 60
Router R2
interface Serial0/0/0
ip ospf hello-interval 15
ip ospf dead-interval 60