I've recently asked a question about my options for load balancing multiple servers (TCP non http traffic, very long running connections with very consistent bandwidth rates): http://serverfault.com/questions/184430/load-balancing-long-running-tcp-connections
In this post I was directed to LVS and just gave that a try. Setup was easy and it pretty much worked right off the bat, with my only issue being that I can only use LVS-NAT (realservers are windows and I do not want to change their config). The problem with that is that it rewrites the source IP, so if a client logs in, I only see the NAT'ed IP and not his original source IP. This poses an issue for us in terms of regulatory requirements as I need to log the real source IP for every client that logs in.
How do others deal with that issue?