Real networks often run multiple routing protocols. Redistribution lets routes from one protocol appear in another.
Common scenarios:
- Merging networks after acquisition
- Connecting to a service provider
- Migrating between protocols
Challenges:
- Metric translation: RIP hop counts don't map to OSPF costs
- Routing loops: Routes redistributed back and forth
- Suboptimal routing without careful metrics
Best practices:
- Redistribute in one direction if possible
- Set administrative distances carefully
- Filter routes to prevent loops