I have two 3725 routers running IOS 12.4. They are both connected different 4500 series switches. The switches are running layer 3 and the networks are subnetted such that it appears that there are different networks connected to each router. They are both in the 10.0.0.0 network but subnetted to different networks. What I want to be able to do is use Network address translation at the 3725. Translating the entire 10.0.0.0 network to the outside. I would like both routers to be doing NAT at the same time as well as acting as backups in case one goes down. I want to use SNAT in order to keep the sessions going should one router go down while traffic is coming in. Each of the 3725s connects back to 3740s and then back to the real world, but the translation has to be done at the 3725s as I don't control the 3740s. It seems like I can accomplish the backup scenario to account for if one goes down while translated traffic is coming in, but I can't find a way to also load balance across the inside links. Any help would be greatly appreciated.
Thank You
