We are able to configure manual summary routes without enabling the car-summary. We are able to also employ a handbook summary if auto-summary is enabled because EIGRP is really a classless routing protocol. Classless routing protocol includes the subnet mask within the routing update and then we can configure manual summarization while using supernet routes. In supernetting, we are able to aggregate multiple routes in a single major classful network address.
Configuring EIGRP Manual Summary Routes
Figure 1 illustrates the topology for manual summary route configuration. This is actually the same topology we’ve already utilized in EIGRP auto-summary configuration. R1 has four adjacent routes and R3 has additionally the 4 adjacent routes. We are able to by hand summarize the routes.
We are able to check out the routing table of R1, R2, and R3 to ensure the EIGRP routes within the routing table for network 10.10.10./30, 10.10.11./24, 10.10.12./24, 10.10.12./24, 172.16../30, 172.16.1./24, 172.16.2./24, and 172.16.3./24. Figure 2 illustrates the routing table of three routers within the above topology, prior to the manual auto-summarization.
Steps for Figuring out Summary Route
To look for the summary route stick to the steps below individually for systems that should summarize.
1.Write all of the network’s binary format that should summarize.
2.Begin with for left in summary all of the systems.
3.Find all of the consecutive matching bits from left to right
4.Mark all of the matching bits in most systems within the column of bits to define the summary boundary.
5.Count the amount of matching bits, which within this example you can observe in figure 3 proven in red and italic.
6.To obtain the network address for summarization, copy the matching bits and add all bits towards the remaining positions to accomplish 32 bits address.
The resultant summary network address and mask for that network of router R1 are 10.10.8./21 but for the network from the router, R2 is 172.16../22.
Configure EIGRP Manual Summarization
We now have found the summary routes for that systems of both routers. To configure EIGRP manual summarization on the specific EIGRP interface, the interface mode command syntax is “Router(config-if)# ip summary-address eigrp <as-number> <network-address> <subnet-mask> “. So let’s configure the EIGRP summary route on R1 and R2.
R1(config)#interface serial //
R1(config-if) ip summary-address eigrp 10.10.8. 255.255.248.
R2(config)#interface serial //1
R2(config-if) ip summary-address eigrp 192.168.. 255.255.252.
The configuration on R1 will propagate the path 10.10.8./21 network on serial // interface. Within the router R2, the configuration will propagate the summary route on serial //1 interface of R2.
Verifying Manual Summary Routes
We are able to verify the summary router configuration by showing the routing table for R2 because both summary routes are propagated towards R2. Figure 4 illustrates the routing table of R2 following the summary route is configured. The routing tables of R2 doesn’t have longer range from the individual route or R1 and R3. Rather, the routing table of R2 displays just one summary route of 172.16../22 and 10.10.8./21.
More router reduce the routing table lookup process efficiency, but summary routes decrease the amount of routes in routing tables which boosts the efficiency. Summary routes also utilize less bandwidth for that routing updates, so just one route could be sent rather of multiple individual routes.