Multiple routing types in one lvs?

["Michael Cunningham" <m.cunningham@xxxxxxxxxxx>]

Hiya,

I was wondering if the following was possible with lvs
and how I could go about implementing it.. 

Current network:

RS1    RS2     RS3   RS4
|            |           |         |
-----------------------
    |        |       |
D1-----D2    |  RS5      RS6
        |            |     |            |
--------------     ----------
            |                     |
            ---------------     

I would like to use DR to route traffic to
RS1-4 and TUN to route traffic to RS5-6

All 6 servers would be in the same pool serving 
out http on port 80 with 1 shared VIP. They are all 
replicas of each other. 

Normally I would like the LVS to only send traffic to
RS1-4 (via a RR or WRR schedule). If all of those 
servers (RS1-4) are not functional then the LVS 
should send traffic RS5-6. 

Is this possible? How could I accomplish this?

Thanks for any assistance you can offer.. 
Mike