How does route redistribution affect routing loops and stability?

• A. It can introduce routes into another protocol and cause loops or suboptimal paths if not carefully filtered or tagged.
• B. It always stabilizes the network by consolidating routes.
• C. It prevents routing loops by isolating routing domains.
• D. It only affects static routes and has no impact on dynamic protocols.

Answer: (A)

Route redistribution tests how injecting routes from one routing protocol into another can affect the entire routing environment. If you redistribute without safeguards, a route learned in one protocol can be exported into another and then reintroduced back into the original protocol. This back-and-forth can create loops or cause the route to bounce, leading to instability, and it often results in suboptimal paths because the two protocols use different metrics and decision processes.

To prevent this, operators tag redistributed routes so they can be identified and avoided on subsequent redistributions. They also apply filtering or route-maps to control exactly which routes get redistributed. By tagging and filtering, you stop routes from being re-redistributed back into their source protocol and you maintain stable, predictable routing decisions across the mixed-protocol environment.