Splitting Supernets for Route Redistribution

TechMason · ‎11-06-2005

I have a router on my LAN that does not accept superneted routes.

So I need to be able to split supernets into classful networks and redistribute them to the LAN interface using RIP2.

How can I do this on IOS 12.3(08)T5?

Example

WAN side routes

200.1.1.0/23

200.1.5.0/24

200.1.10.0/25

should become this on LAN side:

200.1.1.0/24

200.1.1.1/24

200.1.5.0/24

200.1.10.0/25

TIA

Richard Burts · ‎11-06-2005

Mason

I first would like to ask where is the supernet of 200.1.1.0/23 coming from? How is it defined or how does the router learn it? Knowing that might affect the answer of what to do about it.

Would I be correct in assuming that there is a typo in your post and where you have:

200.1.1.0/24

200.1.1.1/24

that you really meant:

200.1.0.0/24

200.1.1.0/24

(the supernet of 200.1.1.0/23 includes the /24s 200.1.0.0 and 200.1.1.0)

My suggestion would be to configure two static routes

on the router. How to configure them (to point to an interface or to point to a next hop) would depend somewhat on where they come from and how the router has learned about them. Then you can redistribute static into rip. This should allow you to configure the classful networks to the neighbor who does not accept supernets.

HTH

Rick

HTH

Rick