[Linux-cluster] LVS: Not as a gateway?

[isplist at logicore.net]

 From what I've seen, LVS can act as an NAT gateway, direct routing or 
tunneling. 

The LVS machines are already under NAT under the firewall's.

I cannot change my web servers to point to LVS as this causes too many 
complications but,  each server does have two Ethernet interfaces.

I cannot really use NAT as the machines are already under NAT to my firewall's 
so, what's the best way of dealing with this without creating another sub 
networking within?

Mike