Use summarization with OSPF to reduce the number
of external routes in the routing table.
Equipment Requirements:
Three Routers
One Switch with two VLANS set or two
switches or two hubs
Two workstations
Scenario:
You have a RIP routing domain and an
OSPF Area 0 with redistribution. You need to reduce the number of RIP
routes that enter your OSPF Area 0. You must configure a
summary-address in OSPF to only advertise one route to the RIP
networks.
Step 1
Cable the lab and all interfaces as
shown in the diagram. You will use loopbacks for the RIP networks.
Step 2
Configure OSPF routing on all routers.
Router-a(config)#router ospf 1
Router-a(config-router)#network 206.202.0.0 0.0.3.255 area 0
Router-b(config)#router ospf 1
Router-b(config-router)# network 206.202.0.0 0.0.3.255 area 0
Verify that OSPF is configured
correctly and all OSPF routes are listed in the routing table. On
Router C the 192.168.1.0-192.168.3.0 networks should be directly
connected, but not listed in the routing table of the other routers.
Step 4
On Router C add the following command
to redistribute all the rip routes into your OSPF Area 0: