I currently Have Debian Lenny running with two network cards installed. I would like to have one nic connected to one router with a gateway of 10.0.0.1 (connected to a DSL line) and another with a gateway of 192.168.1.1 (connected to a T1 line). I would like to setup the server to be able to use both WANs in a load-balancing configuration. I have done some research and have found this page http://www.debianadmin.com/linux-eth...iguration.html
It seems that I can bond the two NICs but that is the extent of my understanding. It seems that ifenslave-2.6 can do what I want, but Im not sure how. Is it possible to have the bond translate between the two networks? If so, how?

You have misunderstood the article you linked to. Bonding doesn't give you 2 network interfaces, it effectively "shares" a single address/gateway with 2 NICs, that way if either card goes bad or a single cable gets unplugged, the other continues to function.

Having 2 NICs with separate addresses and going out separate gateways requires some type of management configuration through software or interfaces. You can't put 2 gateways on one machine and have them simultaneously work, unless you set it up so one interface is used to communicate with one set of addresses and another communicates with another set. You can set the gateways so that one is preferred, but that won't really accomplish what you seem to be looking for.

You can't load balance with one box easily. You could with 2 boxes, but you still need something to handle the 2 internet feeds.

Peace,
JimBass

Thank you very much for your reply. How about if I am able to use the same subnets? Suppose I have the router that goes to the T1 retrieve an IP from the other network (with the same 10.0.0.1 configuration) Would this be easier and possible?
What I need is to be able to load balance the WAN and can effectively forget about the LAN.

The subnet itself isn't the issue, its the multiple gateways. You'd have to ensure that traffic coming in the first gateway goes out the first gateway, and traffic going in the 2nd goes out the 2nd. But doing that destroys the idea of load balancing and redundancy, IE if gateway1 goes down, you still lose that traffic.

You'd have to get fancy with this, and one box is not the way to do it. There's a reason hardware load balancers cost as much or more than automobiles. You can read about advanced routing at this page, but I don't believe it is possible to make this work with one box, 2 NICs and 2 internet connections -

http://lartc.org/lartc.html#LARTC.LOADSHARE

Peace,
JimBass

Ok, I guess I had my hopes up. At least now I can lay the project to rest. I have read that Clarkconnect can do it http://www.clarkconnect.com/docs/Net...gs_-_Multi-WAN Is this more complicated than they make it out to be? I don't care about fail-over. What I want is to not use up my entire T1. That is the main purpose of this idea.

I have installed pfsense and am doing what I needed. If BSD can do it, than I must be able to get my linux box to do it, but until I figure out how to do that, pfsense does what I need, on a very low end system.