network setup help please

dsl----------RB951-2N---------belkin router
|
|
|
(failover)
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cable internet----------buffalo router

how do i set up the 951 to use buffalo router as wan failover .

I guess the order of the RB and the Belkin router are the other way around, since a RouterBoard can not directly connect to dsl.
But to give some advice.
Connect both routers (belkin and buffalo) to dedicated interfaces of the RouterBoard and configure 2 dedicated IP segments between each end.
Then follow this PCC guide to let the RouterBoard load-balance with failover between the two connections

dsl----------RB951-2N---------belkin router

cable internet----------buffalo router

wire connected from buffalo router to rb951-2n for wan failover

can anyone give me a step by step tutorial please , i have no idea how to configure
thanks