Methods For Learning Default Routes in EIGRP
|
Method |
Description |
|---|---|
|
Static route to 0.0.0.0 with the redistribute static command. |
Redistributes/propagates the default static route within the EIGRP routing domain |
|
Using manual summarization with the IP default-network command. |
EIGRP Formerly supported the use of this command. But as this command uses the candidate default flag which the EIGRP no longer supports in recent IOS versions, it is best to not use this command altogether. |
|
Using summary routes with the ip summary-address eigrp <autonomous-system> <address netmask> command on a per-interface basis. |
Manual summarization is configured on a per-interface basis for a specific EIGRP autonomous system. |
Configuring EIGRP Default Route Propagation on Cisco Packet Tracer
Pre-requisite: EIGRP fundamentals, EIGRP Configuration.
With respect to EIGRP or any routing protocol, summarization is a significant tool to create a boundary for query propagation If a router receives a query for a network it does not have in its topology table, it’ll straightaway transmit a reply indicating an unreachable destination (Destination Host Unreachable), without itself going active and propagating the Query further.
Route summarization reduces the amount of routing information that routers must exchange, process, and maintain, which ultimately allows for faster topology convergence and less router load (CPU utilization) within the network. It also restricts the size of an area that is affected by network changes by hiding the changes in the individual networks behind a single advertised summary route.