Experiment 2SB07 Basic Linux Router II Objective • Configure the ...

Experiment 2SB07 Basic Linux Router II Objective • Configure the routing table • Diagnose for various routing problems • Use of the simple PING and TRACEROUTE tools Lab Work Procedure 1. Identify the following in your setup: PC1-x, and Router-x where x is A, B, and C The network connection is shown in the diagram below. PC1-A

Subnet I Network Address: ________________ Subnet Mask: ____________________ Broadcast Address: _______________

eth0 eth0 eth1

Subnet IV Network Address: ________________ Subnet Mask: ____________________ Broadcast Address: _______________

Router A

Subnet VI Network Address: ________________ Subnet Mask: ____________________ Broadcast Address: _______________

eth2

eth1

eth2 eth2

Router B eth1

eth0 eth0

eth0 eth0

PC1-C

PC1-B Subnet II Network Address: ________________ Subnet Mask: ____________________ Broadcast Address: _______________

Router C

Subnet V Network Address: ________________ Subnet Mask: ____________________ Broadcast Address: _______________

Subnet III Network Address: ________________ Subnet Mask: ____________________ Broadcast Address: _______________

Referring to the diagram above, you are given a 24 bit network prefix address 192.168.d.0 and default network mask 255.255.255.0 (where d is the current day of the month). 2. As seen in the diagram, there will be six subnets (I – VI) in the network. What is the minimum number of bits to borrow from the host portion in order to form six subnets?

Checkpoint 3. Assign IP address to the interfaces of Router and PC1 in your group. PC PC1 Router (eth0) Router (eth1) Router (eth2)

Host Address 2 1 1 2

Note: IP address is Network Address + Host Address. Network Configuration 4. Configure IP addresses and netmasks, according to the diagram (refer to the commands and procedures in the previous Lab). 5. Enable IP forwarding on the router. Network Connectivity Test 6. From the router, ping the interfaces of the neighbouring routers which are connected to the local networks to verify the connections are up. These interfaces will be the gateways to outside networks. 7. In the router, use route to view the routing table. How many subnet entries are there? Remember that there are 6 subnets in the whole network. Use sudo /sbin/route add –net netmask gw to manually add the missing subnet entries (Always choose the gateway that is nearest to the destination network. If there are multiple gateways with equal distances to the destination network, choose the one in the anti-clockwise direction in the diagram). Checkpoint 8. Ping to make sure PC1 in your group is connected to PC1s in the other groups. 9. Traceroute to see the path along which the packet is traveling from PC1 in your group to PC1 in the other groups. Trouble Shooting After you finished the last part, the lab supervisor will make one modification to your network connection.

Checkpoint 10. In your group, use ping and traceroute to figure out what and where the problem is. Demonstrate your finding to your lab supervisor once a fault(s) is identified.

11. Determine whether you need to make any modifications to the routing table for your group. If you needed, make the appropriate modification(s).