Chapter 4. Optimizing Routing
There are times when you need to go beyond just turning on a routing protocol in your network. You might need to control exactly which routes are advertised or redistributed, or which paths are chosen. You might also need to use multiple routing protocols. Network performance can suffer when routing is not optimized. Excessive routing updates lead to extra CPU usage because of the amount of routing information and the frequency of updates. Running multiple protocols requires extra router resources and might result in suboptimal paths. Incorrectly configured route filters can lead to routing issues.
Controlling Routing Updates
Cisco IOS provides several ways to control routing updates: ...