Route Distribution of RIP

Redistribution with RIP

R1(config)#router rip R1(config-router)#redistribute static ? metric Metric for redistributed routes route-map Route map reference <cr>

The <cr> is a little misleading here. While the command redistribute static is a complete command, it’s not enough to do the job when redistributing routes into RIP – we need to plant a seed metric. RIP will not understand the metric applied to an OSPF route for example, by planting this seed we are in fact manually setting the metric in a format that RIP understands.

Example:

We know that RIP uses hop count as it’s metric. If we redistribute an OSPF route into RIP that has a cost of 74 – a common OSPF metric – RIP doesn’t want anything to do with that route, since RIP considers a metric of 16 to be ”unreachable”. Therefore we must manually specify the seed metric value.

A good seed metric value for RIP is 2, as the route travels through the RIP domain it will of course increment as per any other route with a dynamic routing protocol.

In a hub and spoke topology, the router connected to both the spoke routers is known as the Border Router. This is the router where will be performing route redistribution.

Example RIP config to enable the redistribution of routes from OSPF into the RIP domain:

R1(config)#router rip R1(config-router)#redistribute ospf 1 metric 2 R1(config-router)#redistribute connected metric 2

More to follow on Route Redistribution from the OSPF spoke router…