✅ What is Route Redistribution?

Route Redistribution is the process of sharing routes between different routing protocols or between different instances of the same protocol.

Think of it like translating languages:

• Imagine you have friends who speak English (OSPF) and others who speak Spanish (RIP).
• You act as the translator (Redistributor) so both groups can understand each other.

In networking, this means allowing routers running different protocols to exchange route information.

🌐 When Do We Use Route Redistribution?

• Merging networks after a company merger (e.g., one uses OSPF, the other RIP).
• Connecting different administrative domains with separate routing protocols.
• Migrating from one protocol to another without downtime.
• Integrating legacy systems with modern networks.

💡 Simple Example: Redistributing RIP into OSPF

bashCopyEditRouter(config)# router ospf 1
Router(config-router)# redistribute rip subnets metric 10

• redistribute rip: Tells OSPF to import routes from RIP.
• subnets: Allows redistribution of subnetted routes.
• metric 10: Assigns a cost to the redistributed routes (OSPF needs this).

🔄 Bidirectional Redistribution Example (OSPF ↔ EIGRP)

bashCopyEditRouter(config)# router ospf 1
Router(config-router)# redistribute eigrp 100 subnets metric 20

Router(config)# router eigrp 100
Router(config-router)# redistribute ospf 1 metric 10000 100 255 1 1500

• metric 20: OSPF cost.
• metric 10000 100 255 1 1500: EIGRP needs multiple metric values:
  • Bandwidth, Delay, Reliability, Load, MTU.