Configuring RIP Route Summarization in Cisco
Pre-requisites: RIP, super netting
Supernetting is mainly used in Route Summarization, where routes to multiple networks with similar network prefixes are combined into a single routing entry, with the routing entry pointing to a Super network, encompassing all the networks. This in turn significantly reduces the size of routing tables and also the size of routing updates exchanged by routing protocols. Route summarization is used to reduce the size of the routing table by creating a single entry for multiple routing entries. Route summarization helps in:
- Saves Bandwidth
- Saves memory
We are going to perform route summarization using RIP.
Step 1: Consider the Topology:
We are going to summarize R1’s loopback addresses, but first, we need to do some configuration on the devices.
Step 3: R1’s configuration
interface FastEthernet1/0 ip address 10.2.0.2 255.255.255.252 no shutdown interface Loopback1 ip address 1.1.1.1 255.255.255.255 interface Loopback2 ip address 1.1.1.2 255.255.255.255 interface Loopback3 ip address 1.1.1.3 255.255.255.255 router rip network 0.0.0.0 no auto-summary
Step 3: R2’s configuration
interface FastEthernet0/0 ip address 10.1.0.2 255.255.255.252 no sh interface FastEthernet1/0 ip address 10.2.0.1 255.255.255.252 no shutdown router rip network 10.2.0.0 no auto-summary
Step 4: R3’s configuration
interface FastEthernet1/1 ip address 10.0.0.2 255.255.255.252 no shutdown interface FastEthernet0/0 ip address 10.1.0.1 255.255.255.252 no shutdown router rip network 0.0.0.0 no auto-summary
Step 5: PC1’s configuration:
ip 10.0.0.1/30 10.0.0.2
Step 6: Now we summarize the loopback address using this command:
int f1/0 ip summary-address rip 1.1.1.0 255.255.255.252
Step 7: Verify whether the summary route is being propagated correctly or not. Checking R3’s routing table:
show ip route
Step 8: Check Connectivity.
To check connectivity perform the following command on PC1: