There are several tools used to modify metrics or route types upon redistribution. Some of these are also used to filter only the routes necessary for redistribution. These tools are…
- Prefix-lists = a mechanism to match on a very large subset of routes
- Distribute-lists = essentially the application of an access-list to the redistribution process
- Route Maps = Used to filter or take specific actions during redistribution
Illustration of the result of route map filtering:
Stuck-in-Active: Journal of an IT-Network Administrator 