Configure OSPF to
function correctly in a non-broadcast environment.
Equipment Requirements:
Two Routers
One Switch with two VLANS set or two
switches or two hubs
Two workstations
Scenario:
You are the network administrator of
the above network, which has 3 sites, connected via a hub and spoke
frame-relay cloud. Both Biloxi and Chicago have PVC's to Abilene. It
is well documented that OSPF behaves quite differently in a
Non-broadcast environment as opposed to a broadcast environment. You
have decided to implement a point-to-multipoint configuration.
Step 1
Cable the lab as shown above. The
device used to simulate a frame relay cloud will be the Adtran unit.
Step 2
Configure the serial interfaces to
match the addressing scheme shown above. Use the first available
address for your Ethernet interfaces. Use multipoint subinterfaces
on the serial connections into the frame cloud. To configure the
subinterfaces issue the following commands:
Abilene(config)#interface serial
0
Abilene(config-if)#encapsulation frame-relay IETF
Abilene(config-if)#no shutdown
Abilene(config)#interface serial
0.101multipoint
Abilene(config-subif)#ip address 172.16.4.1 255.255.255.0
Follow this same procedure with
different addresses on the other two router serial interfaces.
Step 3
Why did we choose to use multipoint
interfaces?
Step 4
Now it is time to complete the
frame-relay configuration. On Abilene, you need to set up the DLCI
for both connections. The connection to Biloxi is DLCI 101 and the
connection to Chicago is DLCI 102. Issue the following commands on
the sub-interface: